(R,R)-1-Acetyl-1′-(2,4,6-trinitro­phen­yl)-2,2′-bipyrrolidine

Katarzyna Eichstaedt; Teresa Olszewska; Maria Gdaniec

doi:10.1107/S1600536812051161

. 2012 Dec 22;69(Pt 1):o144–o145. doi: 10.1107/S1600536812051161

(R,R)-1-Acetyl-1′-(2,4,6-trinitrophenyl)-2,2′-bipyrrolidine

Katarzyna Eichstaedt ^a,^*, Teresa Olszewska ^a, Maria Gdaniec ^b

PMCID: PMC3588260 PMID: 23476399

Abstract

The structure of the title molecule, C₁₆H₁₉N₅O₇, is mainly determined by the steric effect of a bulky 2,4,6-trinitrophenyl group attached to the N atom of a pyrrolidine ring. Both pyrrolidine rings adopt an envelope conformation, with one of the methylene C atoms as the flap in each case, and the N—C—C—N torsion angle along the bond connecting the two pyrrolidine rings is −174.9 (2)°. The benzene ring of the 2,3,5-trinitrophenyl substituent is deformed and the r.m.s. deviation of its six atoms from the best plane is 0.026 Å. The N atoms of the two nitro groups in the ortho positions deviate from the best plane of the benzene ring by −0.033 (5) and 0.385 (5) Å. These groups, as well as the pyrrolidine ring, are twisted relative to the aromatic ring in the same direction, their best planes forming dihedral angles of 30.2 (2), 64.8 (1) and 46.6 (2)°, respectively, with the ring. An intramolecular C—H⋯O hydrogen bond occurs. In the crystal, there is a short [O⋯C = 3.019 (4) Å] contact between a nitro O atom and a C atom of the benzene ring bearing the nitro group and a C—H⋯O interaction between a methyl H atom and another nitro O atom.

Related literature

For crystal structures of related 1-amino-2,4,6-trinitrobenzenes, see: Butcher et al. (1992 ▶); Baggio et al. (1997 ▶).

Experimental

Crystal data

C₁₆H₁₉N₅O₇
M _r = 393.36
Orthorhombic,
a = 8.1989 (5) Å
b = 10.4442 (6) Å
c = 20.8877 (13) Å
V = 1788.63 (19) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 293 K
0.20 × 0.20 × 0.15 mm

Data collection

Oxford Diffraction Xcalibur Eos diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012 ▶) T _min = 0.990, T _max = 1.000
7678 measured reflections
1818 independent reflections
1477 reflections with I > 2σ(I)
R _int = 0.040

Refinement

R[F ² > 2σ(F ²)] = 0.043
wR(F ²) = 0.090
S = 1.06
1818 reflections
254 parameters
H-atom parameters constrained
Δρ_max = 0.14 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2012 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶) and Mercury (Macrae et al., 2006 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Click here for additional data file.^{(27.2KB, cif)}

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812051161/rz5033sup1.cif

e-69-0o144-sup1.cif^{(27.2KB, cif)}

Click here for additional data file.^{(87.7KB, hkl)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812051161/rz5033Isup2.hkl

e-69-0o144-Isup2.hkl^{(87.7KB, hkl)}

Click here for additional data file.^{(7.5KB, cml)}

Supplementary material file. DOI: 10.1107/S1600536812051161/rz5033Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O1	0.98	2.18	2.891 (4)	129
C18—H18C⋯O2ⁱ	0.96	2.51	3.454 (5)	168

Open in a new tab

Symmetry code: (i) Inline graphic .

supplementary crystallographic information

Comment

The title compound was synthesized as a part of a project aiming at the application of 2,4,6-trinitrophenyl chromophore for determination of absolute configuration of secondary diamines. The molecular structure of the title compound is shown in Fig. 1. Both pyrrolidine rings adopt an envelope conformation with the methylene C4 and C9 atoms forming a flap in each of the five-membered rings, respectively. The N7—C6—C2—N1 torsion angle along the bond connecting two pyrrolidine rings is -174.9 (2)°.

The benzene ring of the 2,3,5-trinitrophenyl substituent shows large deformation from planarity with r.m.s. deviation of 0.026 Å for the six fitted atoms and the maximum deviation from the best plane of 0.038 (2) Å for C11. Whereas N3 and N4 atoms of the nitro groups are vitrually in the mean plane of the benzene ring [their deviations from the plane being -0.050 (5), -0.033 (5) Å, respectively] the N1 atom from the pyrrolidine substituent and the N2 atom from one of the ortho nitro groups deviate strongly from this plane [deviations of -0.168 (4) and 0.385 (5) Å, respectively] reflecting steric effects within this overcrowded molecule. The nitro groups attached to C12 and C16 of the benzene ring are twisted in the same direction as the pyrrolidine ring attached to C11 forming the fragment of a propeller. The dihedral angles formed by these nitro groups and the planar C11, N1, C2, C5 fragment are 30.2 (2), 64.8 (1) 46.6 (2)°, respectively. The nitro group attached to C14 is only slightly twisted relative to the benzene ring with the dihedral angle of 4.9 (2)°. The conformation adopted by the molecule leads to two short intermolecular contacts between the pyrrolidine ring H atoms and O toms of the ortho nitro-groups (Table 1). Interestingly, the release of strain in the title molecule occurs differently than in 1-pyrrolidino-2,4,6-trinitrobenzene (Baggio et al., 1997) where the benzene ring adopted a sofa form with the flap formed by the C atom to which the pyrrolidine ring was attached. On the other hand, the release of strain is similar to that observed for N,N-dimethyl-2,4,6-trinitroaniline (Butcher et al., 1992), 1-piperidylo-2,4,6-trinitrobenzene and 1-morpholino-2,4,6-trinitrobenzene (Baggio et al., 1997)

Two short intermolecular contacts are observed in this crystal structure. One, O1···.C16(1/2 + x, 3/2 - y, 2 - z) of 3.019 (4) Å, is formed between the nitro group O atom and the carbon atom of the benzene ring bearing the nitro group. The second one, H18C···.O2(2 - x, 1/2 + y, 3/2 - z) of 2.51 Å, is formed between the methyl group H atom and the nitro group O atom. The crystal packing in the studied crystal is shown in Fig. 2.

Experimental

A mixture of (R,R)-2,2'-bipyrrolidine hydrochloride (280 mg, 1.31 mmol), 1-chloro-2,4,6-trinitrobenzene (650 mg, 2.63 mmol) and anhydrous sodium acetate (860 mg, 10.50 mmol) in anhydrous ethanol (10 ml) was heated under reflux for 30 min. The resulting suspension was cooled to room temperature and water (15 ml) was added into it. The aqueous layer was extracted with dichloromethane (2 x 15 ml). The combined organic extracts were dried over anhydrous magnesium sulfate. Filtration of the drying agent and removal the solvent in vacuo afforded the crude product, which was purified by means of column chromatography on silica gel using ethyl acetate to yield 0.12 g (23%) of product as a yellow solid. Crystals suitable for X-ray diffraction analysis were obtained by allowing a refluxed solution of the product in ethyl acetate to cool slowly at room temperature (without temperature control) and allowing the solvent to evaporate for 20 h, ¹H NMR: (CDCl₃, 500 MHz) δ: 8.66 (s, 2H); 4.49 (q, J=6.8 Hz, 1H); 4.09 (q, J=6.0 Hz, 1H); 3.56 (m, 1H); 3.43 (m, 1H); 3.36 (m, 1H); 3.20 (t, J=8.3 Hz, 1H); 2.10 (m, 2H); 1.92 (s, 3H); 1,88 (m, 5H); 1.73 (m, 1H), [α]_D²⁰ = -1430 (c 0.2 e thyl acetate).