Methyl-l 8«“diamino-3,6-dithiaoctane dihydrochloride.

In document Stereospecific effects of asymmetric ligands in cobalt (III) complexes (Page 165-168)

DL-|Co(tpn)2ox| D-Jco en ox2] F iltra te

i 4- Methyl-l 8«“diamino-3,6-dithiaoctane dihydrochloride.

The dihydrochloride prepared from this optical isomer of the base was recrystallised several times from hot ethanol. It had

[a ]5892 - -5.8°, [a]5780 - -6.5° and [a]&461 - -6.5°. The m.p. was 193

°.

Analyses for 2 H Cl C H N Calculated* 31.46 7.49 10.49 Pounds 31.32 7.64 10.39 £ 4-Methyl-l,8-bis(5,bromosalicylideneimino)3,6-dithiaoctane. The bis-Schiff base of the above 1 -diamine was prepared using 5-bromosal icy 1 aldehyde (prepared after the method of Amvers and

90 \

Burger ). The yellow Schiff base was recrystallised several times from hot ethanol (m.p. 63°).

A n alyses f o r C21H24N2S2°2ß r 2

C H N

C a lc u la te d : 45.00 4 .2 9 5.00 Founds 44.91 4 .1 0 4 .91

d 4-M ethyl- 1 , 8 - d ia m in o - 3 ,6 - d ith ia o c ta n e d i h y d r o - i - d i b e n z o y l t a r t r a t e . Crude d 4 ^ e t h y l - l , 8 - d i a m i n o - 3 , 6 - d i t h i a o c t a n e was re c o v e re d from th e f i l t r a t e o f th e above r e s o l u t i o n by tr e a tm e n t w ith h y d ro c h lo ric a c id th e n sodium h y d ro x id e and f i n a l l y e x t r a c t i o n w ith e t h e r a f t e r th e method d e s c r ib e d ab o v e. This p ro d u c t ( l 2 .1 g ) was d is s o lv e d i n b o i l i n g w a te r 600m l. w ith 1- d i b e n z o y l t a r t a r i c a c id (2 3 .4 g ) and sodium

a c e t a t e ( l 2 g ) . The s o l u t i o n was f i l t e r e d , re d u c ed a t 70° i n a stream o f a i r to 300m l. and s to o d i n th e r e f r i g e r a t o r o v e r n ig h t, The w h ite c r y s t a l l i n e m a te r ia l which s e p a r a te d , was c o l l e c t e d a t th e pump, washed w ith i c e - w a t e r and e th a n o l and d r ie d u n d e r th e lamp

( F r a c tio n l ( a ) , 2 0 g ). The volume o f th e f i l t r a t e was reduced to 100ml. and y ie ld e d d ia s te r e o is o m e r on s ta n d in g ( F r a c tio n 1 ( b ) , 6 . 2 g ) .

F r a c t i o n s l ( a ) and l ( b ) were combined ( 2 6 . 2g) and d is s o lv e d i n b o il i n g w a te r (6 0 0 m l.) c o n ta in in g sodium a c e t a t e (2 0 g ). Three f r a c t i o n s were c o l l e c t e d and a n a ly s e d as d e s c r ib e d above i n “Method f o r Follow ing th e R e s o lu tio n “ (page 1 5 3 ).

F r a c tio n Amount R o ta tio n o f F ree B ase ( [ a ] ^ 8g 3 )

5.7 5 g #45° 14.15g +33° -47° 2 (a ) 2 (b ) 2 (c ) 3 . 3g

F r a c tio n 2 (c ) was d is c a r d e d . F r a c tio n 2 (b ) was r e c r y s t a l l i s e d to g iv e a p ro d u c t ( 9 .6 g ) w hich c o n ta in e d f r e e b a se w ith [a ] 5g9 3 * +45°.

T h is l a s t f r a c t i o n was combined w ith f r a c t i o n 2 (a ) ( t o t a l 1 5 .4 g ) and r e - f r a c t i o n a t e d from b o i l i n g w a te r (5 0 0 m l.) c o n ta in in g sodium a c e ta t e (lO g ) . A s l i ^ i t y e llo w c o lo u r was removed by h e a ti n g th e s o l u t i o n f o r a few m in u te s w ith a c t i v a t e d c h a r c o a l and f i l t e r i n g . T hree f r a c t i o n s were c o l l e c t e d . The t h i r d was d is c a r d e d . The f i r s t

two were a n a ly s e d as above t

F r a c tio n Amount R o ta tio n s ^ 5 8 9 3 F ree B ase S c h if f Base

3 (a ) 6 . 34g +50° 4-35°

3 (b ) 3 .1 g 4-48° 434°

T o ta l y i e l d o f p u re d ia s te r e o is o m e r = 9 .4 g . A n aly ses f o r ( C7H2oN2S2 ^ C18H12°8^

C H IT

C a l c u la te d : 54 .3 5 5.80 5 .07 Found: 54.36 5.79 5 .0 8 d 4 -f tIe th y l-l,8 -d ia m in o - 3 t 6 - d i t h i a o c t a n e .

The d ia s te r e o is o m e r o b ta in e d above ( 9 .0 g ) was decomposed by th e method d e s c r ib e d p r e v io u s ly (page 154) f o r th e o p p o s ite iso m e r, u s in g

t h r e e - q u a r t e r s o f th e amounts re c o rd e d f o r t h a t r e a c t i o n . The y i e l d o f cru d e d -d ia m in e was 2 .8 g (90^a).

d 4-M eth y l- 1 , 8 - d ia m in o - 5 ,6 - d ith ia o c ta n e d ih y d r o c h lo r id e .

The d ih y d r o c h lo r id e o f th e d -d iam in e was p re p a re d i n th e u su a l way and r e c i y s t a l l i s e d s e v e r a l tim e s from h o t e th a n o l .

A nalyses fo r C^H^^gSg. 2 H Cl

C H N

In document Stereospecific effects of asymmetric ligands in cobalt (III) complexes (Page 165-168)