Di­ethyl N,N′ m phenyl­enedioxamate

Acta Cryst.(2003). E59, o825±o827 DOI: 10.1107/S1600536803010225 Itzia I. Padilla-MartõÂnezet al. C₁₄H₁₆N₂O₆

o825

organic papers

Acta Crystallographica Section E Structure Reports Online

ISSN 1600-5368

Diethyl

N

,

N

-

m

-phenylenedioxamate

Itzia I. Padilla-MartõÂnez,a_MarõÂa Chaparro-Huerta,a_{Francisco J.} MartõÂnez-MartõÂnez,a_Herbert HoÈpflb_{and EfreÂn V.} GarcõÂa-BaÂeza_*

a_{Unidad Profesional Interdisciplinaria de}

BiotecnologõÂa, Instituto PoliteÂcnico Nacional, Avenida Acueducto s/n, Barrio La Laguna TicomaÂn, DF 07340, Mexico, andb_{Centro de} Investigaciones QuõÂmicas, Universidad AutoÂnoma de Morelos, Cuernavaca Morelos, Mexico

Correspondence e-mail: vgarcia@acei.upibi.ipn.mx

Key indicators

Single-crystal X-ray study T= 100 K

Mean(C±C) = 0.003 AÊ Rfactor = 0.058 wRfactor = 0.124

Data-to-parameter ratio = 12.1

For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.

#2003 International Union of Crystallography Printed in Great Britain ± all rights reserved

The title compound, C14H16N2O6, crystallizes in the

mono-clinic space group, C2/c. C2 symmetry is imposed on the

molecule. The ethyl oxamate groups are twisted out of the aromatic ring plane by 34.53 (6)_{and both carbonyl groups are} antiperiplanar. The intramolecular hydrogen-bonding pattern is depicted by a soft CÐH O/O0 _{three-centered hydrogen}

bond, and NÐH O and CÐH O hydrogen-bonding

interactions which form anS(5)S(5)S(6)S(6)0_S(5)0_S(5)0_motif. The molecules are linked into C(3) and C(4) chain motifs, forming supramolecular layers in theacplane.

Comment

The title compound, (I), forms monoclinic crystals (C2/c, Z= 4).C2 symmetry is crystallographically imposed on the

mol-ecule; thus only one half molecule is present in the asymmetric unit. The bond lengths and angles are in the standard ranges, with a mean CÐC bond length of 1.384 (3) AÊ (Table 1). The

ethyl oxamate ±N(H)ÐC(O)ÐC(O)ÐOCH2CH3 group is

almost planar, with an N5ÐC5ÐC6ÐO7 torsion angle of 170.2 (2)_{. Both carbonyl groups are antiperiplanar, with an} O5ÐC5ÐC6ÐO6 torsion angle of 170.8 (2)_{. The C5ÐC6} bond distance is almost exactly 1.541 (1) AÊ (Dewar & Schmeizing, 1968), the value usually assumed for a Csp3_ÐCsp3

single bond, while for the Csp2_ÐCsp2_{single bond, the average}

value from the literature (Allenet al., 1987) is 1.478 (12) AÊ. This may be indicative of the absence of conjugation, in spite of the planarity of the oxamate system, but can be justi®ed by steric hindrance; at 2.640 (2) AÊ, the O5 O7 contact is markedly shorter than the sum of the van der Waals radii (3.04 AÊ; Bondi, 1964). The two ethyl oxamate groups are

Received 16 April 2003 Accepted 9 May 2003 Online 16 May 2003

Figure 1

The molecular structure of the title compound, showing the atom-labelling scheme, the three-centered hydrogen-bonding interaction CÐ H O(O0_{) and the H5 O6 H7A hydrogen-bonding interactions.}

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(Fig. 2). These results contrast with those recently reported for the 1,2-isomer,viz. N,N0_{-o-phenylenedioxamate (Martinet al.,} 2002). The analysis of this latter compound reveals a molecule with one ethyl oxamate group synperiplanar and the other antiperiplanar, both twisted with respect to the benzene ring as a result of steric interactions. The above-mentioned conformation allows the formation of the intramolecular three-centered hydrogen-bonding interaction (THB) C1Ð H O5(O50_{). Selected bond distances and torsion angles are} listed in Table 2.

According to graph-set notation (Bernsteinet al., 1995), two adjacent S(6) rings are formed. A particular feature of this interaction is the O5 H1 O50 _{angle of 142 (2), and the} sum of the angles at the donor is 360_{, as required by the} crystallographic symmetry (Fig. 1). The H1 O5 distance [2.45 (1) AÊ] is shorter than the mean value reported for similar systems [2.553 (4) AÊ; Steiner, 2002]; however, it is larger than the values found for other intramolecular THB involving NÐ H as donor [2.09 (2) AÊ; Padilla-MartõÂnez et al., 2001]. These results reveal the relative weakness of the soft CÐH O C interaction (Vargaset al., 2000), compared with the hard NÐ H O C interaction (Desiraju, 1996) involving THB systems. The intramolecular hydrogen-bonding interactions N5ÐH5 O6 and C7ÐH7A O6 (Table 2) complete the overall hydrogen-bonding scheme, which can be depicted as a

set of six hydrogen-bonded rings forming an

S(5)S(5)S(6)S(6)0_S(5)0_S(5)0 _{motif. It is noteworthy that this} last interaction should have some importance in determining

the location of the ethyl group in the oxamate plane. Supra-molecular layers of the title molecule are formed in the ac

plane due to N5ÐH O5i_{[2.17 (2) AÊ] and C7ÐH7B O7}ii

[2.49 (2) AÊ] intermolecular hydrogen bonds (see Table 2 for symmetry codes), which lead toC(4) andC(3) chains motifs, respectively (Fig. 3a), whose topological motif corresponds to a ring graph-set descriptorR22(11)[C(3)C(4)] (Bernsteinet al.,

1995). These parallel chains are generated by translation along the [010] direction (Fig. 3b) and are formed because of the close proximity of alternate acceptors. There are no hydrogen bonds between these layers.

Experimental

The compound was prepared from 2.3 ml (20.4 mmol) of ethyl chlorooxoacetate and 1.0 g (9.3 mmol) of 1,3-diaminobenzene, according to reported procedures (MartõÂnez-MartõÂnezet al., 1998), to yield 20.0 g (70%) of a pale yellow solid (m.p. 425±427 K). IR (KBr, cmÿ1_{): 3349 (NH), 1699 (CO);} 1_{H NMR (300.08 MHz, DMSO-d}

6, p.p.m.): 10.8 (s, 2H, NH), 8.2 (s, 1H), 7.5 (d, 2H), 7.3 (t, 1H), 4.3 (q, 4H, CH2), 1.3 (t, 6H, CH3);13C NMR (75.46 MHz, DMSO-d6, p.p.m.): 161.3 (COO), 156.4 (CON), 138.3 (Ci), 129.6 (Cm), 117.7 (2Co), 113.5

(Co), 63.0 (CH2), 14.5 (CH3). Crystals suitable for X-ray analysis were obtained after slow crystallization from acetone.

Crystal data

C14H16N2O6 Mr= 308.29

Monoclinic,C2=c a= 25.086 (5) AÊ b= 7.1225 (14) AÊ c= 8.2529 (17) AÊ

= 104.870 (3) V= 1425.2 (5) AÊ3 Z= 4

Dx= 1.437 Mg mÿ3

MoKradiation Cell parameters from 600

re¯ections

= 20.0±1.0

= 0.11 mmÿ1 T= 100 (2) K Prism, colourless 0.320.210.20 mm

Data collection

Bruker SMART area-detector diffractometer

'and!scans

5869 measured re¯ections 1607 independent re¯ections 1464 re¯ections withI> 2(I)

Rint= 0.032

max= 27.5 h=ÿ31!32 k=ÿ8!9 l=ÿ10!10

Figure 2

Projection of the molecular structure, showing the twist.

Figure 3

(a) Part of the packing of the title compound, showing the formation of

C(3) andC(4) chain motifs along the [010] direction (R22(11)[C(3)C(4)]);

Re®nement

Re®nement onF2 R[F2_{> 2(F}2_{)] = 0.058} wR(F2_{) = 0.124} S= 1.22 1607 re¯ections 133 parameters

All H-atom parameters re®ned

w= 1/[2_(F

o2) + (0.0415P)2

+ 2.0276P]

whereP= (Fo2+ 2Fc2)/3

(/)max< 0.001

max= 0.36 e AÊÿ3

min=ÿ0.22 e AÊÿ3

Table 1

Selected geometric parameters (AÊ,_).

C1ÐC2 1.385 (2)

C2ÐC3 1.386 (3)

C2ÐN5 1.425 (2)

C3ÐC4 1.382 (3)

C5ÐO5 1.223 (2)

C5ÐN5 1.343 (2)

C5ÐC6 1.543 (3)

C6ÐO6 1.204 (2)

C6ÐO7 1.325 (2)

C7ÐO7 1.468 (2)

C7ÐC8 1.499 (3)

C1ÐC2ÐC3ÐC4 ÿ0.4 (3) N5ÐC2ÐC3ÐC4 ÿ179.55 (18) O5ÐC5ÐC6ÐO6 170.82 (19) N5ÐC5ÐC6ÐO6 ÿ9.6 (3) O5ÐC5ÐC6ÐO7 ÿ9.3 (2) N5ÐC5ÐC6ÐO7 170.22 (15) O5ÐC5ÐN5ÐC2 4.1 (3)

C6ÐC5ÐN5ÐC2 ÿ175.42 (16) C1ÐC2ÐN5ÐC5 37.0 (3) C3ÐC2ÐN5ÐC5 ÿ143.9 (2) O6ÐC6ÐO7ÐC7 4.6 (3) C5ÐC6ÐO7ÐC7 ÿ175.28 (15) C8ÐC7ÐO7ÐC6 ÿ169.18 (17)

Table 2

Hydrogen-bonding geometry (AÊ,_).

DÐH A DÐH H A D A DÐH A

C1ÐH1 O5 0.94 (4) 2.450 (12) 2.896 (2) 108.8 (8) N5ÐH5 O6 0.85 (2) 2.35 (2) 2.734 (2) 108 (2) C7ÐH7A O6 0.95 (2) 2.49 (2) 2.717 (3) 93 (1) N5ÐH5 O5i _{0.85 (2) 2.17 (2) 3.001 (2) 165 (2)} C7ÐH7B O7ii _{0.97 (2) 2.49 (2) 3.361 (3) 149 (2)} Symmetry codes: (i)x;ÿy;1

2‡z; (ii)x;1ÿy;12‡z.

Data collection:SMART(Bruker, 2000); cell re®nement:SMART; data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to re®ne structure: SHELXL97 (Sheldrick, 1997); molecular graphics:

SHELXTL (Bruker, 2000); software used to prepare material for publication:SHELXL97 andWinGX(Farrugia, 1999).

The authors gratefully acknowledge ®nancial support from CGPI±IPN (grant 5201) and CONACYT±MeÂxico (grant 33438-E).

References

Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987).J. Chem. Soc. Perkin Trans.2, pp. S1±19.

Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995).Angew. Chem. Int. Ed. Engl.34, 1555±1573.

Bondi, A. (1964).J. Phys. Chem.68, 441±451.

Bruker (2000).SMART,SAINTandSHELXTL.Bruker AXS Inc., Madison, Winsconsin, USA.

Desiraju, G. R. (1996).Acc. Chem. Res.29, 441±449.

Dewar, M. J. S. & Schmeizing, H. N. (1968).Tetrahedron,11, 96±120. Farrugia, L. J. (1999).J. Appl. Cryst.32, 837±838.

Martin, S., Beitia, J., Ugalde, M., Vitoria, P. & Cortes, R. (2002).Acta Cryst. E58, o913±o915.

MartõÂnez-MartõÂnez, F. J., Padilla-MartõÂnez, I. I., Brito, M. A., Geniz, E. D., Rojas, R. C., Saavedra, J. B. R., HoÈp¯, H., Tlahuex, M. & Contreras, R. (1998).J. Chem. Soc. Perkin Trans.2, pp. 401±406.

Padilla-MartõÂnez, I. I., MartõÂnez-MartõÂnez, F. J., GarcõÂa±BaÂez, E. V., Torres-Valencia, J. M., Rojas-Lima, S. & HoÈp¯, H. (2001).J. Chem. Soc. Perkin Trans.2, pp. 1817±1823.

Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of GoÈttingen, Germany.

Steiner, T. (2002).Angew. Chem. Int. Ed. Engl.41, 48±76.

Vargas, R., Garza, J., Dixon, D. A. & Hay, B. P. (2000).J. Am. Chem. Soc.122, 4750±4755.

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Acta Cryst. (2003). E59, o825–o827 [doi:10.1107/S1600536803010225]

Diethyl

N

,

N

′

-

m

-phenylenedioxamate

Itzia I. Padilla-Mart

í

nez, Mar

í

a Chaparro-Huerta, Francisco J. Mart

í

nez-Mart

í

nez, Herbert

H

ö

pfl and Efr

é

n V. Garc

í

a-B

á

ez

S1. Comment

The title compound, (I), forms monoclinic crystals (C2/c, Z = 4). A C2 symmetry is crystallographically imposed on the

molecule, thus only one half is present in the asymmetric unit. The bond lengths and angles present the usual features,

with a mean C—C bond length of 1.384 (3) Å (Table 1). The ethyl oxamate –N(H)—C(O)—C(O)—OCH2CH3 group is

almost planar, with an N5—C5—C6—O7 torsion angle of 170.2 (2)°. Both carbonyl groups are antiperiplanar, with an

O5—C5—C6—O6 torsion angle of 170.8 (2)°. The C5—C6 bond distance is coincident with that of 1.541 (1) Å (Dewar

& Schmeizing, 1968) usually assumed for a Csp3_—Csp3 _{single bond, while for the Csp}2_—Csp2 _{single bond, the average}

value from the literature (Allen et al., 1987) is 1.478 (12) Å. This can be indicative of absence of conjugation, in contrast

with the planarity of the oxamate system, but can be justified by steric hindrance indicated by the O5···O7 = 2.640 (2) Å

contact that is remarkably shorter than the sum of the van der Waals radii (2.84 Å; Bondi, 1964). The two ethyl oxamate

groups are twisted by 34.53 (6)° away from the aromatic ring mean plane (Fig. 2). These results contrast with those

recently reported for its 1,2-isomer, viz. N,N′-o-phenylenedioxamate (Martin et al., 2002). The analysis of this last

compound reveals a molecule with one ethyl oxamate group synperiplanar and other antiperiplanar, both twisted with

respect to the benzene ring as result of steric interactions. The above-mentioned conformation allows the formation of the

intramolecular three-centered hydrogen-bonding interaction (THB) C1—H···O5(O5′). Selected bonds and dihedral angles

are listed in Yable 2.

According to graph-set notation (Bernstein et al., 1995), two adjacent S(6) rings are formed. A particular feature of this

interaction is the O5···H1···O5′ angle of 142 (2)°, and the sum of the angles measured at the donor is 360 (2)° (Fig. 1).

The H1···O5 distance [2.45 (1) Å] is shorter than the mean value reported for similar systems [2.553 (4) Å; Steiner,

2002]; however, it is larger than the values found for other intramolecular THB involving N—H as donor [2.09 (2) Å;

Padilla-Martínez et al., 2001]. These results reveal the relative weakness of the soft C—H···O═C interaction (Vargas et

al., 2000) respect to the hard N—H···O═C interaction (Desiraju, 1996) involving THB systems. The intramolecular

hydrogen-bonding interactions N5—H5···O6 and C7—H7A···O6 (Table 2) complete the overall hydrogen-bonding

scheme which can be depicted as a set of six hydrogen-bonded rings forming an S(5)S(5)S(6)S(6)′S(5)′S(5)′ motif. It is

noteworthy that this last interaction should have some importance in determining the lying of ethyl in the oxamate plane.

Supramolecular layers of the title molecule are formed on the ac plane due to N5—H···O5i _{[2.17 (2) Å] and C7—}

H7B···O7ii _{[2.49 (2) Å] intermolecular hydrogen bonds (see Table 2 for symmetry codes), which lead to C(4) and C(3)}

chains motifs, respectively (Fig. 3a), whose topological motif corresponds to a ring graph-set descriptor R22_(11)[C(3)

C(4)] (Bernstein et al., 1995). These parallel chains are generated by translation along [010] direction (Fig. 3 b) and

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S2. Experimental

The compound was prepared from 2.3 ml (20.4 mmol) of ethyl chlorooxoacetate and 1.0 g (9.3 mmol) of

1,3-diamino-benzene, according to reported procedures (Martínez-Martínez et al., 1998), to yield 20.0 g (70%) of a pale yellow solid

(m.p. 425–427 K). IR (KBr, cm−1_{): 3349 (NH), 699 (CO);} 1_{H NMR (300.08 MHz, DMSO-d6, p.p.m.): 10.8 (s, 2H, NH),}

8.2 (s, 1H), 7.5 (d, 2H), 7.3 (t, 1H), 4.3 (q, 4H, CH2), 1.3 (t, 6H, CH3); 13_{C NMR (75.46 MHz, DMSO-d6, p.p.m.): 161.3}

(COO), 156.4 (CON), 138.3 (Ci), 129.6 (Cm), 117.7 (2Co), 113.5 (Co), 63.0 (CH2), 14.5 (CH3). Crystals suitable for X-ray

analysis were obtained after slow crystallization from acetone.

Figure 1

The molecular structure of the title compound, showing the atom-labelling scheme, the three-centered hydrogen-bonding

interaction C—H···O(O′) and the H5···O6···H7A hydrogen-bonding interactions. Displacement ellipsoids are drawn at the

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Figure 2

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Figure 3

(a) Part of the packing cell of the title compound, showing the formation of C(3) and C(4) chain motifs growing along the

[010] directions (R22_{(11)[C(3) C(4)]); (b) three-dimensional view of the supramolecular layers of the title compound.}

(I)

Crystal data

C14H16N2O6 Mr = 308.29

Monoclinic, C2/c a = 25.086 (5) Å b = 7.1225 (14) Å c = 8.2529 (17) Å β = 104.870 (3)° V = 1425.2 (5) Å3 Z = 4

F(000) = 648 Dx = 1.437 Mg m−3

Mo Kα radiation, λ = 0.71073 Å Cell parameters from 600 reflections θ = 20.0–1.0°

µ = 0.11 mm−1 T = 100 K Prism, colourless 0.32 × 0.21 × 0.20 mm

Data collection

Bruker SMART area-detector diffractometer

Radiation source: fine-focus sealed tube Graphite monochromator

φ and ω scans

5869 measured reflections 1607 independent reflections

1464 reflections with I > 2σ(I) Rint = 0.032

θmax = 27.5°, θmin = 1.7° h = −31→32

k = −8→9 l = −10→10

Refinement

Refinement on F2 Least-squares matrix: full R[F2 _{> 2σ(F}2_{)] = 0.058} wR(F2_{) = 0.124} S = 1.22 1607 reflections

133 parameters 0 restraints

Primary atom site location: structure-invariant direct methods

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Hydrogen site location: inferred from neighbouring sites

All H-atom parameters refined

w = 1/[σ2_(Fo2_{) + (0.0415P)}2 _{+ 2.0276P]} where P = (Fo2 _{+ 2Fc}2_)/3

(Δ/σ)max < 0.001 Δρmax = 0.36 e Å−3 Δρmin = −0.22 e Å−3

Special details

Experimental. Diffractometer operator H. Höpfl scanspeed_seconds/frame 10 1200 frames measured in phi (0–360) with chi=0 and om=2t h=25 65 frames measured in om (15–35) with chi=280, 2t h=29 and phi=0 Crystal mounted in

perfluorpolyetheroil

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 _{against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F}2_, conventional R-factors R are based on F, with F set to zero for negative F2_{. The threshold expression of F}2 _{> σ(F}2_{) is used} only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2₎

x y z Uiso*/Ueq

H1 0.5000 0.105 (5) 0.7500 0.014 (7)*

C1 0.5000 −0.0276 (4) 0.7500 0.0137 (5)

C2 0.46019 (8) −0.1249 (3) 0.8052 (2) 0.0162 (4)

C3 0.46013 (10) −0.3195 (3) 0.8059 (4) 0.0349 (6)

C4 0.5000 −0.4146 (5) 0.7500 0.0548 (13)

C5 0.39661 (8) 0.1366 (3) 0.7962 (2) 0.0142 (4)

C6 0.35751 (8) 0.2201 (3) 0.8944 (2) 0.0147 (4)

C7 0.30890 (9) 0.4968 (3) 0.9306 (3) 0.0183 (4)

C8 0.28844 (10) 0.6681 (3) 0.8280 (3) 0.0254 (5)

N5 0.41957 (6) −0.0250 (2) 0.8636 (2) 0.0149 (4)

O5 0.40436 (6) 0.21590 (19) 0.67286 (16) 0.0168 (3) O6 0.34333 (6) 0.1378 (2) 1.00371 (18) 0.0220 (4) O7 0.34272 (6) 0.39224 (18) 0.84013 (16) 0.0164 (3)

H3 0.4342 (12) −0.385 (4) 0.844 (3) 0.039 (7)*

H4 0.5000 −0.544 (8) 0.7500 0.075 (16)*

H5 0.4097 (9) −0.068 (3) 0.947 (3) 0.019 (6)*

H7A 0.2805 (9) 0.414 (3) 0.942 (3) 0.014 (5)*

H7B 0.3325 (10) 0.527 (3) 1.040 (3) 0.025 (6)*

H8A 0.2629 (11) 0.634 (4) 0.723 (3) 0.033 (7)*

H8B 0.3183 (11) 0.733 (4) 0.801 (3) 0.034 (7)*

H8C 0.2693 (11) 0.751 (4) 0.893 (3) 0.040 (7)*

Atomic displacement parameters (Å2₎

U11 _U22 _U33 _U12 _U13 _U23

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C4 0.048 (2) 0.0098 (16) 0.123 (4) 0.000 0.052 (3) 0.000 C5 0.0139 (9) 0.0151 (9) 0.0125 (8) −0.0009 (7) 0.0016 (7) −0.0017 (7) C6 0.0120 (9) 0.0173 (9) 0.0137 (9) −0.0017 (7) 0.0015 (7) −0.0009 (7) C7 0.0219 (10) 0.0166 (10) 0.0193 (10) 0.0019 (8) 0.0109 (8) −0.0039 (7) C8 0.0321 (13) 0.0226 (11) 0.0250 (11) 0.0087 (9) 0.0136 (10) 0.0023 (9) N5 0.0137 (8) 0.0172 (8) 0.0144 (8) −0.0005 (6) 0.0047 (6) 0.0015 (6) O5 0.0188 (7) 0.0175 (7) 0.0154 (7) 0.0021 (5) 0.0066 (5) 0.0016 (5) O6 0.0250 (8) 0.0219 (8) 0.0223 (7) 0.0047 (6) 0.0118 (6) 0.0056 (6) O7 0.0195 (7) 0.0143 (7) 0.0172 (7) 0.0028 (5) 0.0077 (5) 0.0001 (5)

Geometric parameters (Å, º)

C1—C2i _{1.385 (2) C5—C6 1.543 (3)}

C1—C2 1.385 (2) C6—O6 1.204 (2)

C1—H1 0.94 (3) C6—O7 1.325 (2)

C2—C3 1.386 (3) C7—O7 1.468 (2)

C2—N5 1.425 (2) C7—C8 1.499 (3)

C3—C4 1.382 (3) C7—H7A 0.95 (2)

C3—H3 0.92 (3) C7—H7B 0.97 (2)

C4—C3i _{1.382 (3) C8—H8A 0.97 (3)}

C4—H4 0.92 (5) C8—H8B 0.96 (3)

C5—O5 1.223 (2) C8—H8C 1.00 (3)

C5—N5 1.343 (2) N5—H5 0.85 (2)

C2i_{—C1—C2 119.9 (2) O7—C6—C5 109.87 (15)}

C2i_{—C1—H1 120.04 (12) O7—C7—C8 106.54 (15)}

C2—C1—H1 120.04 (12) O7—C7—H7A 106.5 (13)

C1—C2—C3 120.25 (19) C8—C7—H7A 113.8 (13)

C1—C2—N5 119.99 (18) O7—C7—H7B 107.1 (14)

C3—C2—N5 119.75 (18) C8—C7—H7B 112.5 (14)

C4—C3—C2 119.1 (2) H7A—C7—H7B 109.9 (19)

C4—C3—H3 120.1 (17) C7—C8—H8A 110.5 (16)

C2—C3—H3 120.7 (17) C7—C8—H8B 110.7 (16)

C3i_{—C4—C3 121.3 (3) H8A—C8—H8B 107 (2)}

C3i_{—C4—H4 119.36 (16) C7—C8—H8C 108.9 (16)}

C3—C4—H4 119.36 (15) H8A—C8—H8C 109 (2)

O5—C5—N5 126.74 (17) H8B—C8—H8C 110 (2)

O5—C5—C6 121.17 (17) C5—N5—C2 123.78 (16)

N5—C5—C6 112.08 (15) C5—N5—H5 117.7 (16)

O6—C6—O7 126.36 (17) C2—N5—H5 118.5 (16)

O6—C6—C5 123.76 (17) C6—O7—C7 116.45 (14)

C2i_{—C1—C2—C3 0.22 (18) N5—C5—C6—O7 170.22 (15)}

C2i_{—C1—C2—N5 179.3 (2) O5—C5—N5—C2 4.1 (3)}

C1—C2—C3—C4 −0.4 (3) C6—C5—N5—C2 −175.42 (16)

N5—C2—C3—C4 −179.55 (18) C1—C2—N5—C5 37.0 (3)

C2—C3—C4—C3i _{0.22 (17) C3—C2—N5—C5 −143.9 (2)}

supporting information

sup-7

N5—C5—C6—O6 −9.6 (3) C5—C6—O7—C7 −175.28 (15)

O5—C5—C6—O7 −9.3 (2) C8—C7—O7—C6 −169.18 (17)

Symmetry code: (i) −x+1, y, −z+3/2.

Hydrogen-bond geometry (Å, º)

D—H···A D—H H···A D···A D—H···A

C1—H1···O5 0.94 (4) 2.45 (1) 2.896 (2) 109 (1)

N5—H5···O6 0.85 (2) 2.35 (2) 2.734 (2) 108 (2)

C7—H7A···O6 0.95 (2) 2.49 (2) 2.717 (3) 93 (1)

N5—H5···O5ii _{0.85 (2) 2.17 (2) 3.001 (2) 165 (2)}

C7—H7B···O7iii _{0.97 (2) 2.49 (2) 3.361 (3) 149 (2)}