(Z)-N-[1-(Aziridin-1-yl)-2,2,2-tri­fluoro­ethyl­idene]-4-bromo­aniline

Alexander S Bunev; Maksim A Vasiliev; Gennady I Ostapenko; Alexander S Peregudov; Victor N Khrustalev

doi:10.1107/S1600536814007867

. 2014 Apr 12;70(Pt 5):o550. doi: 10.1107/S1600536814007867

(Z)-N-[1-(Aziridin-1-yl)-2,2,2-trifluoroethylidene]-4-bromoaniline

Alexander S Bunev ^a,^*, Maksim A Vasiliev ^a, Gennady I Ostapenko ^a, Alexander S Peregudov ^b, Victor N Khrustalev ^c

PMCID: PMC4011223 PMID: 24860358

Abstract

The title compound, C₁₀H₈BrF₃N₂, crystallizes with two independent molecules in the asymmetric unit, which can be considered as being related by a pseudo-inversion center, so their conformations are different; the corresponding N=C—N—C torsion angles are 54.6 (5) and −50.5 (5)°. In the crystal, molecules related by translation in [001] interact through short intermolecular Br⋯F contacts [3.276 (2) and 3.284 (2) Å], thus forming two types of crystallographically independent chains.

Related literature

For applications of aziridines, see: Tanner (1994 ▶); Remers & Iyengar (1995 ▶); Armstrong et al. (1996 ▶); Katoh et al. (1996 ▶); Schirmeister (1999a ▶,b ▶); McCoull & Davis (2000 ▶). For the crystal structures of related compounds, see: Chinnakali et al. (1998 ▶); McLaren & Sweeney (1999 ▶); Zhu et al. (2006 ▶); Moragas Solà et al. (2010 ▶).

Experimental

Crystal data

C₁₀H₈BrF₃N₂
M _r = 293.09
Monoclinic,
a = 11.642 (2) Å
b = 8.5455 (16) Å
c = 11.846 (2) Å
β = 116.106 (3)°
V = 1058.3 (3) Å³
Z = 4
Mo Kα radiation
μ = 3.90 mm⁻¹
T = 120 K
0.30 × 0.25 × 0.25 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2003 ▶) T _min = 0.388, T _max = 0.442
13846 measured reflections
6146 independent reflections
5186 reflections with I > 2σ(I)
R _int = 0.043

Refinement

R[F ² > 2σ(F ²)] = 0.047
wR(F ²) = 0.118
S = 1.01
6146 reflections
289 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 1.97 e Å⁻³
Δρ_min = −0.86 e Å⁻³
Absolute structure: Flack (1983 ▶), 2866 Friedel pairs
Absolute structure parameter: 0.025 (11)

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2001 ▶); data reduction: SAINT (Bruker, 2001 ▶); program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536814007867/cv5449sup1.cif

e-70-0o550-sup1.cif^{(28.3KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814007867/cv5449Isup2.hkl

e-70-0o550-Isup2.hkl^{(300.8KB, hkl)}

Click here for additional data file.^{(4.1KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814007867/cv5449Isup3.cml

CCDC reference: 996162

Additional supporting information: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors are grateful to the Ministry of Education and Science of the Russian Federation (State contract No. 426).

supplementary crystallographic information

1. Comment

Aziridines are important heterocyclic compounds present in unusual natural products that display strong biological activity (Tanner, 1994; McCoull & Davis, 2000). For instance, azinomycines A and B isolated from the fermentation broth of Streptomyces griseofuscus and (+)-FR900482 isolated from the culture broth of Streptomyces sandaensis are potent antitumor antibiotics that exhibit exceptional activity against various types of mammalian solid tumors. Mitomycin C is an aziridine-containing antibiotic produced by Streptomyces caespitosus, whose antineoplastic activity is associated with the high reactivity of the strained aziridine ring (Remers & Iyengar, 1995; Armstrong et al., 1996; Katoh et al., 1996). Recently novel types of peptidic cysteine protease inhibitors containing aziridine-2,3-dicarboxylic acid have been designed and synthesized (Schirmeister, 1999a,b).

In this work, a new substituted aziridine, C₁₀H₈BrF₃N₂ (I), was prepared by the reaction N-(4-bromophenyl)-2,2,2-trifluoroethenecarbonimidoyl chloride with aziridine at room temperature (Figure 1), and its structure was unambiguously established by the X-ray diffraction study (Figure 2).

The title compound I crystallizes in chiral monoclinic space group P2₁ with two crystallographically independent molecules in the unit cell. The two crystallographically independent molecules represent different conformers distinguishing by rotation of the aziridine substituent around the ordinary (CF₃)C—N bond (the corresponding N1—C1—N2—C3 and N3—C11—N4—C13 totsion angles are 54.6 (5) and –50.5 (5)^o, respectively). The bond lengths and angles in I are in a good agreement with those found in the related compounds (Chinnakali et al., 1998; McLaren & Sweeney, 1999; Zhu et al., 2006; Moragas Solà et al., 2010). The molecule of I is the Z-isomer relative to the double C═N bond. The p-bromo-phenyl substituent is twisted by 38.42 (12) and 39.61 (10)% (for the two crystallographically independent molecules, respectively) relative to the double bond plane. Tha absolute structure of I was objectively determined by the refinement of Flack parameter, which has become equal to 0.025 (11).

In the crystal, the molecules of I form infinite chains along [001] by the intermolecular secondary Br1···F1ⁱ (2.276 (2) Å) and Br2···F5ⁱⁱ (3.284 (2) Å) interactions (Figure 3) [symmetry codes: (i) x, y, 1 + z; (ii) x, y, –1 + z]. The chains consist of the conformationally similar molecules and arranged at van der Waals distances.

2. Experimental

To a mixture of aziridine (1.29 mL, 1.075 g, 25 mmol), triethylamine (3.48 mL, 2.525 g, 25 mmol), and benzene (35 mL) was added slowly (20 min) a solution of N-(4-bromophenyl)-2,2,2-trifluoroethenecarbonimidoyl chloride in benzene (50 mL). The mixture was stirred for 5 h. The triethylamine hydrochloride was filtered, and the solvent was evaporated to give of crude product. Yield is 75%. The single-crystal of the product I was obtained by slow crystallization from EtOAc/Hexane (1:9). M.p. = 324–325 K. IR (KBr), ν/cm^-1: 3408, 1715, 1629, 1492, 1295, 1200, 1155, 996, 828, 531. ¹H NMR (600 MHz, DMSO-d₆, 304 K): 7.56 (d, 2H, J = 8.2), 6.99 (d, 2H, J = 8.7), 2.21 (br. s, 4H). Anal. Calcd for C₁₀H₈BrF₃N₂: C, 33.54; H, 1.41. Found: C, 33.61; H, 1.52.