GOC-1+Lecture+Notes+VIPUL

ORGANIC CHEMIS TRY

TOPIC : GOC - I

LECTURE NOTES

Session - 2009-10

CONTENTS

:

1

IUPAC Nomenclature

Refer sheet GOC- I

JEE Syllabus [2009]

Concepts: Hybridisation of carbon; Sigma and pi-bonds; Shapes of molecules; Structural and

geometrical isomerism; Optical isomerism of compounds containing up to two asymmetric

cen-ters, (R,S and E,Z nomenclature excluded); IUPAC nomenclature of simple organic compounds

(only hydrocarbons, mono-functional and bi-functional compounds); Conformations of ethane

and butane (Newman projections);

IUPAC NOMENCLATURE

1.1

INTRODUCTION TO ORGANIC COMPOUNDS:

-Organic compounds are compounds of carbon and hydrogen and the following elements may also be present: (Halogens, N, S, P, O). There are large no. of organic compounds available and large no of organic compounds are synthesized every year.The most important reason for large no of organic compounds is the property of catenation (self–linkage) in carbon.

Element Bond Energy

C C–C (strongest bond)

Si Si–Si

Ge Ge–Ge _Decreasing order

Sn Sn–Sn

Pb Pb–Pb

Bond energy depends on

(i) Size of atom (Inversely proportional) Size : C–C>Si–Si

(ii) E.N difference along period (Directly) E.N Diff : C – H < N – H < O – H < H – F (iii) Bond order (no. of covalet bonds b/w two atoms) (Directly) Bond order : C – C < C = C < C C

Catenation in

carbon:-The element carbon has strongest tendency to show catenation or self–linkage due to – (a) its tetravalency so that it can form  bonds with many elements as well as carbon itself.

(b) It can form multiple bonds (C = C, C  C). Due to its small size, there is efficient colateral overlapping b/w two P–orbitals.

Does not exist

(c) High bond energy of C – C bond so that it can form strong bonds in long chains and in cylic compounds.

Ex. Compounds Classification Unsaturated Heterocyclic , saturated Unsaturated Saturated Saturated, Alicylic

1.3

IMPORTANT TERMS:

Saturated compounds:

When all the valencies of an element are satisfied by  covalent bonds. Unsaturated compound:

When a compound contains one or more  bonds (C = C, C = N, N = N, C = O or C  C, C  N, N  N) Molecular Formula (M.F.) :

The molecular formula of a compound indicates the actual number of atoms of each element present in one molecule.

Structural Formula (S.F.):

It indicates the linkage due to covalent bond between different atoms in a molecule. (i) Expanded Structural Formula (E.S.F.)

(ii) Condensed Structural Formula (C.S.F.) (iii) Bondline Structural Formula (B.S.F.)

Ex. M.F. C₃H₈ Ex. M.F. C₄H₁₀ E.S.F. H H H H H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H H H – C – C – C – H _E.S.F. H H H H H H H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H H H – C – C – C – C – H C.S.F. CH₃– CH2– CH3 C.S.F. CH3– CH2– CH2– CH3 B.S.F. or B.S.F. Ex. B.S.F. Ex. B.S.F. C.S.F. CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 CH 3– CH – CH – CH2 3 CH3 M.F. C₆H₁₂ M.F. C₅H₁₂ Homologous series :

Homologous series may be defined as a series of similarly constituted compounds in which the members possess the same functional group, have similar chemical characteristics and have a regular gradation in their physical properties. The two consecutive members differ in their molecular formula by CH₂.

Calculation of Degree of Unsaturation

(b) ) O DU ( CH – C H – C H_{3 2 3}     –2H –2HCH₃– C  CH or CH2 = C = CH2 or

That means Deficieny of 2H is equivalent to 1 DU

(c) (i) 1DU = Presence of 1 Double Bond or Presence of 1 Ring closure

(ii) 2DU = Presence of 2 Double bond or 1 Triple bond or two ring closure or 1 double bond + 1 ring.

(d) G.F. D.U. (i) C_xH_y (x + 1) –       2 y (ii) C_xH_yO_z (x + 1) –        2 o y (iii) C_xH_yX_s (x + 1) –        2 s y (iv) C_xH_yN_w (x + 1) –       2 w – y (v) C_xH_yO_zX_sN_w (x + 1) –        2 w – s y

Ex Calculate DU of following compounds (a) C₆H₆O DU = 4 (b) C₆H₅Cl DU = 4 (c) C₆Br₆ DU = 4 (d) C₅H₁₁OCl DU = 0 (e) C₉H₁₂N₂ DU = 5 (f) C₆N₆ DU = 10 (g) C₁₀H₈SO₅ N₄Cl₂ DU = 8 e.g. M.F. DU S.F. 1. C₄H₆ 2 C–C=C=C H H H H H H C – C – C  C C – C  C – C C = C – C = C C C CH2

2. C₂H₂Cl₂ =1

Total isomers = 3

3. C₇H₆O (Aromatic) = 5

4. C₇H₈ (Aromatic) = 4

Note : In case of the aromatic Compounds minimum DU = ‘4’. That means at least 1 Benzene ring is present.

Degree of carbon :

It is defined as the number of carbon atoms attached to a carbon atom.

Primary (1°) carbon : | H | H 1° Secondary (2°) carbon : Tertiary (3°) carbon : | | H C 3° Quaternary (4°) carbon : | | C C 4° Superprimary : (1°) Ex. CH – C – CH – CH – CH3 2 3 | CH3 | CH3 | CH3 1 2 3 4 5 1 – 5 carbon 2 – 1 carbon 3 – 1 carbon 4 0 0 0 0 – 1 carbon

Ex.

*Degree of hydrogen

is same as the degree of carbon to which it is attached.

Type of C – C bonds & type of replaceable H-atoms in saturated hydrocarbon.

Note : Total no. of monosubstituted product does not depend upon type of C-atoms but depends upon type of replaceable H-atoms.

1.4

IUPAC NOMENCLATURE OF ORGANIC COMPOUNDS:

General Scheme of

Naming:-Secondary Prefix + Primary Prefix _ _Word Root_ _Primary Suffix_ _Naming:-Secondary suffix

The organic compound is always named according to the general scheme as given by IUPAC. In every compound, two parts, viz, word root and primary suffix, always exist.

Word Root

: It indicates the no. of carbon atoms present in the main chain. It is represented as Alk.

Prefix

: It is the first part of the name. (i) Primary Prefix : ‘Cyclo’

(ii) Secondary Prefix : Normal substitutents and junior functional groups are treated as a substituent than their name is treated as secondary prefix.

The following substituent groups are always cited in the prefix. (i) R – Alkyl

(ii) R – O – Alkoxy

(iii) X halo (fluoro, chloro, bromo, iodo) (iv) –NO₂ Nitro

(v) –N = O Nitroso (vi) Junior functional group

The prefixes are always written in alphabetical order

The position of substituent group in the main carbon chain is mentioned by writing the number just before the name of substituent by writing a small dash (–).

Suffix :

(i) Primary Suffix:- It indicates saturation or unsaturation existing in the main chain. ane  single bond (saturated)

ene  one = bond

diene  If two double bonds

Polyene  if plenty of double bond are present. yne  one  bond

diyne  two  bond

(ii) Secondary Suffix:- It is used for the principal functional group.

1.5

NAMING OF SATURATED HYDROCARBONS

Rules :(Branched and substituted Alkanes)

(1) Selection of parent chain 

(b) If number of carbon atoms are same in more than one longest chain then more substituted longest chain will be the parent chain.

(c) If number of side chain are also same then that will be parent chain having its substituent at lower number.

C – C – C – C – C – C – C – C C C – C – C C C

(2) Numbering

(a) Numbering is done from that side of the parent chain having it substituent at lower number (lowest set of locant)

(b) If position of substituent are same from both the end of the parent chain, then numbering is done from alphbetical order.

* If alphabets are also same then numbering is done from that side of the parent chain having its substituent of substituent at lower number.

Ex. – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 – CH3 CH – CH – CH3 3 Methylpropane – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 – CH3 CH 3– CH – CH – CH3 2, 3-Dimethyl butane – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 – CH3 CH 3– C – CH3 Dimethyl propane 2-Methylbutane

– C – C – C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C C – C – C – C – C– C 3-Ethyl-2-methyl hexane – C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C C – C – C – C – C– C – C – C 4, 4-Diethyl heptane – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C C – C – C – C – C – C – C – C – C

4, 4-Diethyl-2, 5-Dimethyl heptane

– C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C C – C – C – C – C 3-Ethyl hexane CH₃– CH2– CH2– CH2Cl 1-Chlorobutane – Br C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl 3-Bromo-2-chloropentane – Br C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl C – C – C – C – C – Cl 2-Bromo-4-chloro pentane – Br C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl C – C – C – C – C – – Cl Cl

4-Bromo-2, 2-dichloro pentane

– Br – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl C – C – C – C – C – C – Cl

5-Bromo-2, 3-dichloro hexane

(3) Rules for writing Alkyl

Radicals:-Radicals:- (a) C_nH_{2n + 2} –H C_nH_{2n + 1} Alkyl Radical

C_nH_2n –H C_nH_2n

– 1 Alkenyl Radical

C_nH_{2n – 2} –H C_nH_{2n – 3} Alkynyl Radical

R (structural formula) Name

CH₃– Methyl

(b) CH – C – CH3 3 | CH3 | H – H – H | CH3 | H CH – C – CH – Isobutyl3 2 | CH3 | CH – C – CH3 3 Tert butyl (Tertiary butyl) 3 2 1

(4) Systematic Names of Radicals :

Complex Radical :

Ex 5 – ( 1,2 – Dimethylpropyl) nonane

5 – (1,1 – Dimethylpropyl) nonane

5 – (1 – Ethylpropyl) nonane

5 – (Dimethylethyl) nonane

Alkene / Alkyne radicals

Alkene Alkenyl Alkyne Alkynyl CH₂ = CH₂ CH₂ = CH – ethenyl CH₃– CH = CH2 Prop – 1 – enyl Methylethenyl Prop – 2 – enyl

CH₃– C  CH CH3– C  C – Prop-1-ynyl CH₃– C  CH – CH₂– C  C – H Prop-2-ynyl

(5) Benzene Radical

1. Phenyl 2. Benzyl 3. Benzal 4. Benzo 5. CH3 Tolyl (o, m, p)



Methylene 7. Alkylidene 8. - naphthyl 9. -naphthyl

(6) Numeral Prefixes

(1) Following prefixes are considered for alphabetization :

(a) Iso

(b) neo

(c) Di, Tri, Tetra of complex radical are considered for alphabetization (2) Following are not considered for alphabetization

(a) Di, Tri, Tetra for simple radicals.

(b) Sec, Tert are not considered for alphabetization (c) Bis , Tris

(7) Retained Names of Alkanes:

(1) Normal (n) : Radical or hydrocarbon which has straight chain and if it has free valency it must be present at either of ends.

C – C – C – C (n butane)

(2) Iso : Two methyl group at the end of linear chain (unbranched chain)

(i) C – – C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C

C– C Isobutane or methyl propane

(ii) C – – C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C – C Isopentane or methylbutane (iii) C – – C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C – C – C Isohexane or 2-methylpentane Conditions

:-There should be 4 to 6 carbon atoms only

There should not be any other alkyl group present in the chain. Q. Iso-octane (commercial name) in petroleum industry

Ans. C – – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – – C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C– C C

– C IUPAC name is 2, 2, 4-trimethylpentane

(3) Neo : There should be 5 to 6 carbon atoms 2, 2-dimethyl No other substituent. Ex. C – – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C Neopentane C – – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C C – C – C Neohexane

(4) Secondary : It is applicable only for radical. Ex.1

(5) Tertiary :

First member

1.6

NAMING OF UNSATURATED COMPOUND (ALKENES AND ALKYNES) :

(A) General formula:- C_nH_2n and C_nH_{2n – 2} respectively (B) Rules for selection of main

chain:- Longest carbon chain with a multiple bond.

 Longest carbon chain with maximum number of multiple bonds.

 If first and second factor are common then chain with lowest locant (multiple bond) is selected as main chain.

 Lowest locant Rule is followed till first point of difference. (Multiple bond prior to substituent).  Alphabetization.

(C) Rules for

Numbering:- Lowest locant Rule till first point of difference (irrespective of double bond or triple bond).

 Then double bond is prefer over triple bond in numbering, naming and longest chain selection, If all the other factors are common

Ex. CH₃– CH2– CH = CH2 But-1-ene CH₃– CH = CH – CH3 But-2-ene – CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 CH3 CH 3– CH – CH – CH = CH2 2 4-Methylpent-1-ene CH 3– CH – CH = CH – CH3 CH3 | 4-Methylpent-2-ene – 6 5 4 3 2 1 – Cl Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 Cl CH 3– C – CH – CH – CH = CH2 2 2 5, 5-Dichlorohex-1-ene (a) C = C – C = C Buta-1,3-diene (b) C  C – C  C Butadiyne (c) C = C – C  C Butenyne 1 2 3 4 5 6 C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C C C – C – C = C – C Hex-4-en-1-yne 1 2 3 4 5 6 Hexa-1, 3, 5-triene

Ex.1 3-(2-Methylpropyl) hept-1-ene

Ex.2 4 -(1,1-Dimethylpropyl)-4-ethenylhepta-1,5-diene

Ex.3 3-Ethynylhexa-1, 5-diene

Ex.4 4-Ethenylhept-2-en-5-yne

Ex.5 4-(1, 2-Dimethylbutyl) hept-2-en-5-yne

Ex.6 2, 4-Dimethylpenta-1, 3-diene

Ex.6 2,3-Dimethylhex-1-en-4-yne

1.7

NAMING OF CYCLIC HYDROCARBON (ALICYCLIC COMPOUNDS) :

(A) Main chain selection:

(a) Multiple Bond > No. of carbon atoms > Maximum no. of substituents > Nearest locant > Alphabetization. (b) If all factors are similar in cyclic and acyclic part, then Cyclic > Acyclic

(B) Numbering:

(a) Lowest Locant (b) Alphabetization

(C) Naming:

Prefix ‘cyclo’ is used just before the word root if it constitutes the main chain.

If cyclic part is the main chain then the prefix ‘cyclo’ is not considered for alphabetical order..

If cyclic part constitutes the side-chain (substituent) then prefix cyclo is considered for

Cyclopentane Cyclohexane Cycloheptane Cyclooctane ––––––––––––––– Methylcyclopropane Ethylcyclopropane Propylcyclopropane 1-Cyclopropylbutane – C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – – C – Cl C – C – Cl 2-Chloroethylcyclopropane – Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C– Cl – C – C Chloroethylcyclopropane 3 2 1 – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl 1-Chloro-3-cyclopropylpropane 1 2 3 – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl 2-Chloro-1-cyclopropylpropane 1 2 3 – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl – C – C – C – Cl 1-Chloro-1-cyclopropylpropane – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C – – Cl C – C – C 1-Chloro-2-propylcyclopropane Cl Br F I 1 2 3 4 – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – 2-Bromo-1-chloro-3-fluoro-4-iodocyclohexane Methylethylcyclopropane or isopropylcyclopropane Cl Br I 1 2 5 6 3 4 – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – 1-Bromo-2-chloro-4-iodocyclohexane Cl 1 2 3 4 5 6 3-Chlorocyclohex-1-ene Cl 1 2 3 4 5 6 _Br 5-Bromo-3-chlorocyclohex-1-ene

1.8

FUNCTIONAL GROUP TABLE (Seniority order):

1.9

NAMING OF FUNCTIONAL GROUP CONTAINING COMPOUNDS :

(A) Selection of Main Chain:

Senior F.G. > Max. no. of F.G. (Similar group) > Multiple bond > Max. no. of ‘C’ atoms > Max. no. of locants > lowest locant > alphabetization

(B) Numbering (See F.G. + Sub.):

The carbon atom bearing functional group (or C – atom of terminal functional group) is given lowest possible number.

(i) Lowest locant (F.G. > M.B. > substituent > Alphab)

(C) Naming:- General scheme :

The senior most functional group constitutes secondary suffix. Other junior F.G.’s are written as prefix in alphabetical order. Class R – COOH R – SO₃H R – C – O – C – R || || O O R – COOR R – C – X || O R – C – NH₂ || O R – C  N R – C – H || O R – C – R || O R – OH R – SH R – NH₂ Name Alkanoic acid

Alkane sulphonic acid Alkanoic anhydride Alkyl alkanoate Alkanoyl halide Alkanamide Alkanenitrile Alkanal Alkanone Alkanol Alkanethiol Alkanamine Suffix

– oic acid (carboxylic acid) – sulphonic acid

– anhydride

– alkanoate (carboxylate)

– oyl halide (carbonyl halide)

– amide (carboxamide) – nitrile (carbonitrile) – al (carbaldehyde) – one – ol – thiol – amine Prefix Carboxy sulpho ---Alkoxy carbonyl halo carbonyl Carbamoyl cyano formyl / Oxo Oxo / Keto hydroxy mercapto amino 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.

1.9.1

Carboxylic acid

F.G. Prefix Suffix IUPAC name

– COOH Carboxy

Oic acid - 'C' of COOH considered in the parent chain

Carboxylic acid - 'C' of COOH is not considerd in parent chain

Alkanoic acid

Alkane carboxylic acid

Rule : If first alphabet of sec. suffix is begin from a, i, o, u, y then ‘e’ of primary suffix will be dropped.

Ex. (1) HCOOH Methanoic Acid

(2) CH₃– COOH Ethanoic Acid

(3) C – C – COOH Propanoic Acid

(4) C – C – C – COOH Butanoic Acid

(5) 2 3 4 5 6 1 C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH C – C – C – C – C – C – C – C COOH 2-propylhexanoic acid (6) – COOH – COOH – COOH – COOH – COOH – COOH – COOH – COOH – COOH – COOH – COOH – COOH – COOH – COOH – COOH Cyclopropanecarboxylic acid (7) 2 1 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 – CH – COOH2 Cyclopropylethanoic acid (8) 1' 2' 3' – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH – – C – C – C COOH COOH –

4-(2-carboxypropyl) cyclohexane-1-carboxylic acid

(9) HOOC – COOH Ethanedioic acid

(10) HOOC – CH2– COOH Propanedioic acid

(11) HOOC – CH2– CH2– CH2– CH2– COOH Hexanedioic acid

(12) Cycloprop-1-ene-1, 2, 3-tricarboxylic acid

1.9.2

Sulphonic acid

F.G. Prefix Suffix IUPAC name

– SO3H Sulpho Sulphonic acid Alkanes sulphonic acid

Ex. (1) CH₃– SO₃H Methanesulphonic acid

(2) C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 C – C – C – C – C – SO H3 Pentane-2-sulphonic acid

(3) –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 –SO H3 Cyclobutanesulphonic acid

(4) HOOC HOOC HOOC HOOC HOOC HOOC HOOC HOOC HOOC HOOC HOOC HOOC HOOC HOOC HOOC 1 2 3 4 5– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H– C – C – C – C – SO H333333333333333 5-Sulphopentanoic acid

1.9.3

Anhydride

(a) O O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O R – C – O – H + H – O – C – R O H – Heat 2      R – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C – O – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C – R



Alkanoic anhydride

(b) Mixed Anhydride (according to alphabet)

acid Ethanoic COOH – CH₃ + Acid opanoic Pr COOH – CH – CH3 2 _ CH₃– O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– O – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– C2H5

Ethanoic propanoic anhydride Ex. (1) H – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C – O – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C – H ) unstable ( Anhydride Methanoic (2) O C C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O C C – C – C – O – C – C – C O 2-Methylpropanoic anhydride (3) Butanedioic anhydride (4) C – C – C – C – O – C – C – C – C || O || O Butanoic anhydride (5) C C O || O || O

Cyclohexane-1, 2-dicarboxylic anhydride

(6) O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O – C – O

Cyclopropane carboxylic anhydride

1.9.4

Ester :

F.group Prefix Suffix Name

– O C O C O C O C O C O C O C O C O C O C O C O C O C O C O

C– OR Alkoxy Carbonyl Oate Alkyl....alkanoate

or or or

(Ester) Alkanoyloxy carboxylate Alkyl...Alkanecarboxylate

O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R' O R – C – O – H + H – O – R'–H2O O R – C – O – R' Example:- (1) H – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– O – CH3 Methyl methanoate (2) C – C – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– O – C – C – C Propyl propanoate (3) C – C – O – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– C – C – C Ethyl butanoate (4) C – C – C– C– C– C– C– C– C– C– C– C– C– C– C– C– C – C – O – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– H Isobutyl methanoate (5) O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 O C – O – C – C – C – COOH 3 2 1 3-(Methoxycarbonyl)propanoic acid (6) C – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O

C– O – C – C – COOH 3-(Ethanoyloxy)propanoic acid

(7)

2-(Methoxycarbonyl)-4-(Propanoyloxy) cyclohexan-1-carboxylic acid

(8) O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O – O C _– – O –

Cyclopropyl benzene carboxylate

(9)

O

O = C

OCH3

– –

– O – C – CH – CH2 3 Methyl-3-propanoyloxy cyclohexane carboxylate

1.9.5 Acid

halide:-F.Group – C – X Name Alkanoyl halide or

Alkane carbonyl halide

Prefix Halo Carbonyl Suffix Oyl-halide or Carbonylhalide O Example:- (1) O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl– O = C – Cl–

(2) CH₃– O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– Cl Ethanoyl chloride (3) Prop-2-enoyl bromide

(4) 6-Methyl hept-4-en-2-ynoyl chloride

(5) – O CH – 2– CH – CH – CH – C – Cl2 2 – O COOH C Cl – – – – – – – – – – – – – – 5, 5-Dichlorocarbonylpentanoic acid (6) O – – COOH COOH – C – Cl

3-Chlorocarbonyl cyclopropane-1, 2-dicarboxlic acid

(7) C – CH – CH – CH = CH – CH – COCl2 2

–

O

CH3

Cl

– 5-Methylhept-3-ene-1, 7-dioyl Chloride

(8) 4-Bromocarbonyl-2-chlorocarbonyl-5-propanoyloxycycloexane-1-carboxylic acid

1.9.6

Amide:-F.Group – C – NH2 Name Alkanamide or Alkane Carboxamide Prefix Carbamoyl Suffix amide or Carboxamide O Example:- (1) H – O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– NH2 Methanamide (Formamide) (2) CH₃– O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– NH2 Ethanamide (Acetamide) (3) CH₃– O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C– NH – CH3 N-methylethanamide (4) C C C C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C O – CH3– C – N – C – C – C N-butyl-N-propylethanamide

(5) – O = C – NH2 Benzene carboxamide (6) O – – O = C – NH2 C – NH2 Benzene-1, 3-dicarboxamide (7) – COOH – C – NH2 O

3-Carbamoyl cyclohexane-1- carboxylic acid

(8) O O CH2 C – NH – CH3 C – NH – CH3

N, N’-Dimethyl propane-1, 3-diamide

1.9.7

Nitrile:-Example:- (1) H – CN Methanenitrile (2) CH₃– CN Ethanenitrile (3) CH 3– CH – CH – CN2 CH3 – 3-Methyl butanenitrile (4) – – – CN CN CN Cyclopropane-1, 2, 3-tricarbonitrile (5) – CN – CN – CN – CN – CN – CN – CN – CN – CN – CN – CN – CN – CN – CN – CN Benzene carbonitrile (6) – CN CH – CH – COOH2 2

3-Cyano propanoic acid

(7) – CN CH 2– CH – – CH2 CN – CN Propane-1,2,3-tricarbonitrile

1.9.8

Isocyanide

:-F.Group – N C Name Alkyl Isocyanide Prefix Isocyano Suffix Isocyanide

Example:- (1) CH₃– N  C Methyl isocyanide

(2) CH₃– CH2– N  C Ethyl isocyanide (3) – NC – NC – NC – NC – NC – NC – NC – NC – NC – NC – NC – NC – NC – NC – NC Phenyl isocyanide

1.9.9

Aldehyde:-F.Group – CH = O Name Alkanal or Alkane Carbaldehyde Prefix Formyl or oxo Suffix al or carbaldehyde

Example:- (1) HCHO Methanal

(2) CH₃– CH2– CH = O Propanal (3) CCl₃– CH2– CH2– CH2– CH = O 5, 5, 5-Trichloro pentanal (4) – CH = O Cyclohexane carbaldehyde (5) CH = O ––––––––––––––– Benzaldehyde/Benzene carbaldehyde (6) CH – _{– CH –} – – CH Cl2 Ph Ph CH = O

2-Chloromethyl-3, 3-diphenyl propanal

(7) CH = O CH = O – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – Benzene-1, 3-dicarbaldehyde

(8) HOOC – CH2– CH2– CH2– CH = O 5-Oxopentanoic acid

(9) HOOC – CH – CH – CH – COOH2 2

CH 2– CH = O

–

3-(2-Oxoethyl) pentane-1, 5-dioic acid

(10)

–

–

CH 2– CH – CH = O2

COOC H2 5

1.9.10

Ketone:-F.Group C = O Name Alkanone Prefix Keto or oxo Suffix one – – Example:- (1) CH₃– C O – CH₃ Propanone (2) O Cyclohexanone (3) O O O Cyclohexane-1, 3, 5-trione (4) – O O CH – C – CH2 3 2-(2-Oxopropyl) cyclohexanone (5) O – – CH – CH – C – CH2 2 3 COOH

3-(3-Oxobutyl) cyclohexane -1-carboxylic acid

(6) OHC – CH2– C O – CH3 3-Oxobutanal

1.9.11

Alcohol:-F.Group –OH Name Alkanol Prefix Hydroxy Suffix ol Example:- (1) CH – CH – CH – OH3 2 CH3 – 2-Methyl Propanol (2) CH 3_{– CH – CH – CH – CH – CH}2 2 3 CH – _{2– OH} CH– _{2 –} OH 2, 5-Dimethylhexane-1, 6-diol (3) – – OH OH – – – – OH HO OH HO Cyclohexane-1, 2, 3, 4, 5, 6-hexaol (4) – CH 2– OH CH – OH –

CHO (Glyceraldehyde) 2, 3-Dihydroxy propanal

(5) Cl– CH – CH – CH – CH – CH – OH2 2 2 2 Cl– CH – CH – CH2 2 _– – OH – OH– CH 3– CH – CH2 2

(6) O O O _– OH – – HO OH

2, 4, 6-trihydroxy cyclohexane-1, 3, 5-trione

(7) _– OH CH 2– CH – – CH2 OH – OH

(Glycerol) Propane-1, 2, 3-triol

1.9.12

Amines:-F.Group –NH2 Name Alkan amine Prefix amino Suffix amine

(a) R – NH2 1º = amine Alkanamine

(b) R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H R – N – R' H 2º = amine ) R ( ) ' R ( e min a Alkylalkan N (c) R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' R – N – R' R' 3º = amine N, N-Dialkylalkanamine (d) R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 R – N – CH3 CH 2– CH3 N-Ethyl-N-methylalkanamine Ex:- (1) CH₃– NH2 Methanamine (2) C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 C – C – C – C – C – NH2 Pentan-3-amine (3) C – C– C – NH – C – C N-Ethylpropan-1-amine (4) C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C C – C – C – N – C – C N-Ethyl-N-methylpropan-1-amine (5) C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C C – C – C – NH – C – C N-Ethylpropan-2-amine (6) – CH 2– CH = CH – CH – CH3 OH – NH – CH – CH2 3

4-(N-Ethyl amino) pent-2-en-1-ol

(7) OHC – CH – CH – CH – CH2 – 2 3

NH – Ph

3-(N-Phenyl amino) pentanal If hetero atom’s are count as a ‘C’ atom in the parent chain then they are written as (1) –NH– Aza

(2) –O– Oxa (3) –S– Thia (4) –Se Selena

Example:- (1) HOOC – CH2– NH – CH2– CH3 3-Aza pentanoic acid

(2)

H N–

(3) N H – – CH3

3-Methyl aza cyclo hexane

1.10

ETHERS (R

–

O

–

R

’

):-F.Group R – O – R' Name Alkoxy alkane Prefix alkoxy Suffix – ' C ' of . no less Alkoxy  + ' C ' of . no more Alkane 

(i) Acyclic

Ethers:-(1) C – O – C Methoxymethane (2) C – O – C – C Methoxyethane (3) C – O – C – C – C 1-Methoxypropane (4) C – C – C – O– O– O– O– O– O– O– O– O– O– O– O– O– O– O – C 2-Methoxypropane (5) C – C – C – O – C – C– C– C– C– C– C– C– C– C– C– C– C– C– C– C – C 1-Isopropoxypropane 1-(Methylethoxy) propane (6) – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} – _{O – C – C} Ethoxycyclohexane (7) – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} – _{O –} Cyclopropoxycyclohexane (8) 4 – Cl 1 2 3 5 6 – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br – – – O – C – C – C OH Br 3-Bromo-6-chloro-2-propoxycyclohexan-1-ol

 In cyclic system, numbering always starts from senior most functional group.

(9) 4 – 1 2 3 5 6 – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH OH Br – – O – CH3 OH Br 6-Bromo-5-methoxycyclohex-2-en-1-ol (10) 4 – 1 2 3 5 6 – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br – – O – C – C OH Br 6-Bromo-5-ethoxycyclohex-3-en-1-ol

(ii) Cyclic Ether: (3-membered Ring) Hetero cyclic compounds

(1) O C – C O C – C O C – C O C – C O C – C O C – C O C – C O C – C O C – C O C – C O C – C O C – C O C – C O C – C O C – C Oxirane or Epoxyethane (2) O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C 1, 3-Epoxypropane (3) O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C 1, 2-Epoxypropane (4) Cl – O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C O C – C – C 1-Chloro-2, 3-Epoxypropane  Polyethers:-(1) C – C – O – C – C 1 2 – O – C – C 1, 2-Diethoxyethane (2) C – C – O – C – C – O – C – C – O – C – C 1 2 3 4 5 6 7 8 9 10 11 3, 6, 9-Trioxaundecane (3) C – O – C – C – C – O – C – C – O – C – C – C – O – C – C1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 2, 6, 9, 13-Tetraoxapentadecane (4) O O O O 1 2 3 4 5 6 7 8 9 10 11 12 1, 4, 7, 10-Tetraoxacyclododecane

1.11

AROMATIC COMPOUNDS:

Classification:

Non-Benzenoid:

 H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – – H H H + – – –

Cation 2 e– _{Cyclopropenium ion}

 H H + – – – – H H + – – – – H H + – – – – H H + – – – – H H + – – – – H H + – – – – H H + – – – – H H + – – – – H H + – – – – H H + – – – – _H H + H H + – – – – H H + – – – – H H + – – – – H H + – – – – H H + – – – –

 -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H -H H H . . – – – – – _H H

Anion 6 e– _{Cyclopentadienyl anion}

 – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – _– – _– H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H – – – H H H H + H H

6 e– _{Cycloheptatrienyl cation (Tropylium cation)}

Benzenoid Aromatic Compounds:

All organic compounds which contain atleast one benzene ring are known as benzenoid aromatic com-pounds.

Naming of Aromatic Hydrocarbons (Arenes):

(1) CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – CH3 – Methylbenzene (Toluene) (2) CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _– CH3 CH3 – _–

(Ortho) 1, 2-Dimethylbenzene (Ortho-xylene)

(3) CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 –

– (Meta) 1, 3-Dimethylbenzene (Meta-xylene)

(4) CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – – CH3 CH3 – –

(Para) 1, 4-Dimethylbenzene (Para-xylene)

Q. Write structures of (i) Metadiethylbenzene C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – C – C C – C – – (ii) 1-ethyl-4-isopropylbenzene C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – C – C C – C – C – – (iii) Orthodiethenylbenzene C = C C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –_{C = C} C = C – –

Trialkyl Substituted Benzene:

If all the three substituents are similar, then only 3 trisubstituted benzene derivative are possible.

C C C – – – C C C – – – C C C – – – C C C – – – C C C – – – C C C – – – C C C – – – C C C – – – C C C – – – C C C – – – 1, 2, 3-Trimethyl benzene (Vicinal Trimethyl benzene)

C C C – – – C C C – – – C C C – – – C C C – – – C C C – – – 1, 2, 4-Trimethyl benzene (Unsymmetrical Trimethyl benzene)

C C C – – – C C C – – _C– C C – – _C– C C – – _C– C C – – _C– C C – – _C– C C – – _C– C C – – _C– C C – – _C– C C – – _C– C C – – – 1, 3, 5-Trimethyl benzene (Symmetrical Trimethyl benzene)

C C C – – _C– C C – – _C– C C – – _C– C C – – _C– C C – – –

Examples : 1. C – C C– – Isopropylbenzene (Cumene) 2. Cl NO2 C – – – 1-Chloro-4-methyl-2-nitrobenzene 3. C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C

Phenylethene (Double bond > Phenyl) (Common name : Styrene)

4. C – C = C – 3-Phenylprop-1-ene (Allylbenzene) 5. CH = CH – CH3 – 1-Phenylprop-1-ene 6. COOH –

Benzene carboxylic acid (Benzoic acid)

7.

C – O – C

– _–

O O

Benzene carboxylic anhydride (Benzoic anhydride)

8.

SO H3

–

Benzene sulphonic acid

9.

C – O – C H2 5

–

O

Ethyl benzene carboxylate (Ethyl Benzoate)

10. O – C – CH3 – O Phenyl ethanoate 11. C – Cl – O

Benzene carbonyl chloride (Benzoyl chloride)

12. NH – C – CH3 – O N-Phenylethanamide 13. C – NH – CH3 – O N-Methylbenzene carboxamide

14.

C N

–

Benzene carbonitrile (Benzonitrile – popular)

15.

CH = O

–

Benzene carbaldehyde (Benzaldehyde – popular)

16.

C

– _–

O

Diphenyl ketone (Benzophenone)

17.

C

– _–

O

CH3 Methyl phenyl ketone (Acetophenone)

18. – OH Phenol 19. – ––– CH3 OH

Methylphenol [o-Cresol, m-cresol, p-cresol]

20. – – OH OH o-Hydroxyphenol (Catechol) 21. – – OH OH m-Hydroxyphenol (Resorcinol) 22. – – OH OH p-Hydroxyphenol (Quinol)(Hydroquinone) 23. – NH2 Benzenamine (Aniline) 24. – SH Benzenethiol 25. – C – O – H O O O – C – CH3

ORGANIC CHEMIS TRY

TOPIC : GOC - I

LECTURE NOTES

Session - 2009-10

CONTENTS

:

1

Isomerism

* Structure Isomerism

* Stereo Isomerism

Geomertical

Optical

Conformational

Refer sheet GOC- I

JEE Syllabus [2009]

Concepts: Hybridisation of carbon; Sigma and pi-bonds; Shapes of molecules; Structural and

geometrical isomerism; Optical isomerism of compounds containing up to two asymmetric

cen-ters, (R,S and E,Z nomenclature excluded); IUPAC nomenclature of simple organic compounds

(only hydrocarbons, mono-functional and bi-functional compounds); Conformations of ethane

and butane (Newman projections);

Isomerism

Isomers:

Compounds with same general formula or molecular formula but different physical and chemical property. Ex:- CH₃– CH2– OH and CH3– O – CH3

Ex:- CH₃–COOH and HCOOCH3

Homologs:

Compounds with same general formula differing by same structural unit – CH2– or molecular weight by 14 unit.

Ex:- CH₃– OH and CH3– CH2– OH

homologs:-Structural isomers:

When two or more number of organic compounds have same molecular formula but different structural formula these are called structural isomers.

Stereo isomers:

When two or more compounds have same Molecular Formual (M.F.) and same Structural Formula (S.F.) but have different stereochemical formula (S.C.F.), these are called stereoisomers.

Stereo Chemical Formula (S.C.F) :

It indicates different arrangements of atoms or groups in space around a stereo centre or it indicates different spatial orientations of atoms or groups around a stereo centre.

M.F. C₄H₈

S.F. (i) CH₃– CH2– CH = CH2 (ii) CH3– CH = CH – CH3 (iii)

CH3

CH 3– C = CH2

–

These are structural isomers. For (ii), S.C.F. are

H C3 CH3 H C = CC = CC = CC = CC = CC = CC = CC = CC = CC = CC = CC = CC = CC = CC = C H and H C3 CH3 H H Stereocentre C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C C = C

These are stereoisomers.

Structural isomers are also known

as:-(i) Skeletal isomers (ii) Linkage isomers (iii) Constitutional isomers

Chain isomers :

They have different size of main carbon chain and / or side alkyl chain

(i) The two chain isomers should have same nature of F.G./multiple bonds/substituents (except –R group) (ii) The position of F.G./M.B./substituent (locants) is not. considered here.

Ex:-

Alkanes:-(a) C₁– C₃ chain isomers not possible

(b) C₄H₁₀ H₃C – CH2– CH2– CH3 and CH3– – CH3

(c) C₅H₁₂ CH₃– CH2– CH2– CH2– CH3 , CH3– CH2– – CH3 , CH3– – CH3

(d) C₆H₁₄ (i) CH₃– CH₂– CH₂– CH₂– CH₂– CH₃, (ii) CH₃– CH – CH₂– – CH₃,

(iii) CH₃– CH2– – CH2– CH3, (iv) CH3– – – CH3,

(v) CH₃– CH₂– – CH₃ (i) and (ii) – Chain isomers

(i) and (iii) – Chain isomers (i), (iv) – Chain isomers (i), (v) – Chain isomers (ii), (v) – Chain isomers (ii), (iii) – Position isomers (iv), (v) – Position isomers

Ex. and shows which types of isomerism ?

Q. Write chain isomers of N-alkanamine (1º) containing 4 carbon atoms ? Ans. C – C – C – C – NH₂, C – C

C_–

– C – NH₂

Positional isomers:

They have different position of locants Functional group (F.G.) or Multiple Bond (M.B.) or substituents in the same skeleton of C-atoms.

Nature of F.G. or M.B. should not change. The skeleton of C-atom should not change. Ex. (1) C – C – C – C C_– – C , C – C – C C_– – C – C (2) C = C – C – C , C – C = C – C (3) C  C – C – C – C , C – C  C – C – C (4) C – C – OH– C – C , C – C – C – C – OH Q. Write all Positional isomers of Dichlorobenzene ?

Ans. Cl Cl – – , Cl Cl – – , Cl Cl – –

Q. Write all Positional isomers of Dichlorocyclopropane ?

Ans. – – Cl Cl , – – Cl Cl

Q. Write all Positional isomers of Dichlorocyclobutane ?

Ans. – – Cl Cl , – – Cl Cl , – – Cl Cl

Q. Write all Positional isomers of Dichlorocyclopentane ?

Ans. – – Cl Cl , – – Cl Cl , – – Cl Cl Ex. (i) C – C – C – C C – – C – C – C (ii) C – C – C C_– – C C_– – C – C, (iii) C – C C_– – C – C – C C_– – C

(i), (ii) – Chain (ii), (iii) – Position (i), (iii) – Chain Ex. C₆H₁₂ (Cycloalkanes):-(1) , (2) – , (3) – – , (4) – – ,

(5) – – – , (6) – – , (7) – C – C – C , (8) – C – C – C , (9) – C – C – , (10) – – –, (11) –C – C

Ans. (3) and (4) – Positional isomer (3) and (6) – Positional isomer (4) and (6) – Positional isomer (5) and (10) – Positional isomer (All are chain isomers of 1) Remaining are chain isomers

Functional isomers:

They have different nature of functional group (F.G.). The chain and positional isomerism is ignored (not considered).

Compound Functional isomer

C – C – C – C Nil

C – C – C = C (Ring-chain isomers are Functional isomers)

Ex. Compound Isomer Functional Remarks

(1) C – C – C  C (a) C = C – C = C Alkadiene (a), (b) are not functional isomers

Alkyne (b) Cycloalkene among themselve

(c) Bicyclo (2) C – C – C – OH C – C – O – C Alcohol Ethers (3) C – C – CH = O C – C O – C Aldehydes Ketones (4) C – C – COOH C – C O – O – C Carboxylic acids Esters

(5) C – C – C – NH2 (a) C – C – NH . . – C (b) C – C N – . .

– C 1º, 2º, 3º amines are functional isomers 1º amine 2º amine 3º amine

(6) C – C – C  N C – C – NC

Cyanide Isocyanide

(Propanenitrile) (Ethane isocyanide)

Important point :- Following compounds don’t exist at room temperature therefore not consider as a structure isomer (i) – – C – C – C – C – C – C – C – C – C – C – C – C – C – C – C = – C – C – C – C – C – C – C – C – C – C – C – C – C – C – C– OH (ii) – C  C – OH (iii) – OH– – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – OH (iv) – OR– – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – OH (v) – OH– – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – – C – – –

Q. Write acyclic isomers of C₅H₁₂O

Ans. (i) C – C – C – C – C – OH, C – C – C – OH– C – C, C – C – OH– C – C – C, C – C – C C_– – C – OH, C – C C– – C – C – OH, C – C C_– C– – C – OH, C – C – C C_– C– – OH (7 alcohols) C – C – C – C – O – C, C – C – C C_– – O – C, C – C C_– – C – O – C, C – C C_– C_– – O – C, C – C – C – O – C – C, C – C C_– – O – C – C (6 ethers). Q. G.F. n M.F. C_nH_{2n + 3}N (1) 3 C₃H₉N

1º Amine (R – NH₂) 2º Amine (R – NH – R) 3º Amine R – N – R

–

R

Q G.F. n M.F.

C_nH_{2n + 1}N (1) 2 C₂H₅N

2

1º Amine 2º Amine 3º Amine

(1) C = C – NH2 C – C = N C – N = C

Ethenamine Ethanimine N-Methylene methanamine

(Unstable at room temperature)

N H H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – H C 2 _–– CH2 – – Azine Q. G.F. n M.F. C_nH_2n – 1N 2 C2H3N

Ans. Cyanides and isocyanides

H₃C – C  N CH2 = C = NH HC  C – NH2

H₃C – N  C

Metamers:

When two isomers have same functional group (containing a hetero atom –O, N, S) but have different nature of alkyl or aryl (aromatic radical) group attached to hetero atom, then these are called metamers.

Conditions:

(a) Same functional group

(b) Chain or position isomerism is not considered. (c) >C = O (keto) group does not show metamerism Following functional groups show metamerism

(a) R – O – R’ Ethers (All isomeric ethers are metamers) (b) R’ – NH – R 2º Amines

(c) R’ – N

R''

––––––––––––––– – R 3º Amines