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Acta Crystallogr Sect E Struct Rep Online. 2010 August 1; 66(Pt 8): o1889–o1890.
Published online 2010 July 3. doi:  10.1107/S1600536810025080
PMCID: PMC3007260

2-(4-Methyl­cyclo­hex-3-en­yl)propan-2-yl N-phenyl­carbamate

Abstract

In the title carbamate compound, C17H23NO2, one of the Csp 3 atoms of the cyclo­hexene ring is disordered over two sites with refined occupancies of 0.55 (2) and 0.45 (2), both disorder components resulting in half-boat conformations. The mean plane through the carbamate unit is inclined at inter­planar angles of 14.80 (13), 18.30 (17) and 24.0 (2)°, respectively, with respect to the phenyl ring, and the major and minor disorder component cyclo­hexene rings. In the crystal structure, adjacent mol­ecules are linked into chains along [001] via inter­molecular N—H(...)O hydrogen bonds. The crystal structure is further stabilized by weak inter­molecular C—H(...)π inter­actions.

Related literature

For general background to and applications of the title compound, see: Banerjee et al. (1978 [triangle]); Graia et al. (2009 [triangle]); Ibuka et al. (1985 [triangle]); Lapidus et al. (1987 [triangle]); Loev & Kormendy (1963 [triangle]); Muradov et al. (1986 [triangle]); Niu et al. (2007 [triangle]); Ibuka et al. (1985 [triangle]). For related carbamate structures, see: Garden et al. (2007 [triangle]); Graia et al. (2009 [triangle]). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 [triangle]).

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Object name is e-66-o1889-scheme1.jpg

Experimental

Crystal data

  • C17H23NO2
  • M r = 273.36
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1889-efi1.jpg
  • a = 19.3067 (19) Å
  • b = 9.0058 (9) Å
  • c = 8.9521 (9) Å
  • β = 100.964 (3)°
  • V = 1528.1 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 100 K
  • 0.58 × 0.20 × 0.10 mm

Data collection

  • Bruker APEXII DUO CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.957, T max = 0.992
  • 8744 measured reflections
  • 2205 independent reflections
  • 2053 reflections with I > 2σ(I)
  • R int = 0.049

Refinement

  • R[F 2 > 2σ(F 2)] = 0.050
  • wR(F 2) = 0.154
  • S = 1.15
  • 2205 reflections
  • 187 parameters
  • 4 restraints
  • H-atom parameters constrained
  • Δρmax = 0.68 e Å−3
  • Δρmin = −0.76 e Å−3

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810025080/hb5524sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810025080/hb5524Isup2.hkl

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

Acknowledgments

The authors would like to acknowledge Universiti Sains Malaysia (USM) for the University Grant (No. 1001/PTEKIND/8140152). HKF and JHG thank USM for the Research University Golden Goose Grant (No. 1001/PFIZIK/811012). JHG also thanks USM for the award of a USM fellowship.

supplementary crystallographic information

Comment

Carbamates are well-known class of compounds with biological activity (Muradov et al., 1986). They can be prepared by different methods, for example by nickel-catalyzed coupling of CO2 and amines (Niu et al., 2007), by stirring of alcohols including steroids as well as primary and secondary alcohols, polyols, phenols with sodium cynate, and trifluoroacetic acid (Loev & Kormendy, 1963), by carbonylation of aromatic nitro compounds (Lapidus et al., 1987), by the reaction of isocynates with alcohols (Ibuka et al., 1985) in the presence of lewis acid and by the reaction of an amine and an alcohol with phosgene. Phytosterol, β-Sitosterol, stigmasterol and cholesterol react with phenyl isocyanate to give carbamate (Banerjee et al., 1978; Graia et al., 2009). In this study the title compound has been synthesized by the reaction of α-terpineol with phenylisocyanate in the presence of catalytic amount of HCl in chloroform solvent.

In the title carbamate compound (Fig. 1), atom C10 of the cyclohexene ring (C9-C14) is disordered over two sites with a refined occupancy ratio of 0.55 (2):0.45 (2). The major (C9/C10A/C11-C14) and minor (C9/C10B/C11-C14) disordered cyclohexene rings adopt the same conformation, that is the half-boat conformation; puckering parameters Q = 0.427 (4) Å, θ = 57.4 (5)°, [var phi] = 335.9 (7)° for major disordered component and Q = 0.651 (6) Å, θ = 131.6 (4)° and [var phi] = 161.7 (7)° for minor disordered component. The mean plane through the carbamate moiety (N1/C7/O1/O2) is inclined at interplanar angles of 14.80 (13), 18.30 (17) and 24.0 (2)°, respectively, with respect to the C1-C6 phenyl ring, major and minor disordered cyclohexene rings. The bond lengths and angles are comparable to those related carbamate structures (Garden et al., 2007; Graia et al., 2009).

In the crystal structure, intermolecular N1—H1N1···O2 hydrogen bonds (Table 1) link adjacent molecules into one-dimensional chains running along the [001] direction (Fig. 2). Further stabilization of the crystal structure is provided by weak intermolecular C13—H13A···Cg1 interactions (Table 1) involving the centroid of the C1-C6 phenyl ring.

Experimental

A mixture of α-terpineol (1.640 ml) and phenylisocyanate (1.087 ml) in 1:1 molar ratio were stirred in chloroform for 30 minutes in the presence of catalytic amount of HCl. The reaction mixture was dried on rota vapor at low pressure and then chromatographed over silica gel column loaded in light petroleum ether. The column was eluted only with light petroleum ether to give five fractions of the title compound. These fractions were mixed together on the basis of same TLC results and crystallized with chloroform:alcohol (1:1) to give the colourless needles of (I) (1.93 g, M.p. 378 K). The melting point was taken on Thermo Fisher digital melting point apparatus of IA9000 series and is uncorrected. Open column chromatography was performed on silica gel 60 (Merck, 0.040–0.063 mm, 230–400 mesh ASTM) and Sephadex LH-20 (Pharmacia). TLCs were taken on silica gel plates (silica gel 60 F254 on aluminum foil, Merck).

Refinement

Atom C10 is disordered over two sites with a refined occupancy ratio of 0.55 (2):0.45 (2). Atom C10B of the minor disordered component was refined isotropically. The C—C bond lengths in the minor disordered component were restrained with distance of 1.50 (1) Å. All H atoms were placed in their calculated positions, with N—H = 0.86 and C—H = 0.93 or 0.96 Å, and refined using a riding model, with Uiso = 1.2 Ueq(N) and Uiso = 1.2 or 1.5 Ueq(C). The rotating group model was applied to the methyl groups. In the absence of significant anomalous dispersion, 1491 Friedel pairs were merged in the final refinement.

Figures

Fig. 1.
The molecular structure of (I), showing 30 % probability displacement ellipsoids. Open bonds indicate the minor disordered component.
Fig. 2.
The crystal structure of (I), viewed down the b axis, showing molecules being linked into one-dimensional chains along the c axis. Minor disordered component and H atoms not involved in intermolecular hydrogen bonds (dashed lines) have been omitted for ...

Crystal data

C17H23NO2F(000) = 592
Mr = 273.36Dx = 1.188 Mg m3
Monoclinic, CcMo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2ycCell parameters from 2414 reflections
a = 19.3067 (19) Åθ = 3.3–32.4°
b = 9.0058 (9) ŵ = 0.08 mm1
c = 8.9521 (9) ÅT = 100 K
β = 100.964 (3)°Needle, colourless
V = 1528.1 (3) Å30.58 × 0.20 × 0.10 mm
Z = 4

Data collection

Bruker APEXII DUO CCD diffractometer2205 independent reflections
Radiation source: fine-focus sealed tube2053 reflections with I > 2σ(I)
graphiteRint = 0.049
[var phi] and ω scansθmax = 30.0°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −26→27
Tmin = 0.957, Tmax = 0.992k = −12→11
8744 measured reflectionsl = −12→12

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.050H-atom parameters constrained
wR(F2) = 0.154w = 1/[σ2(Fo2) + (0.0981P)2 + 0.223P] where P = (Fo2 + 2Fc2)/3
S = 1.15(Δ/σ)max < 0.001
2205 reflectionsΔρmax = 0.68 e Å3
187 parametersΔρmin = −0.76 e Å3
4 restraintsExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.044 (6)

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(F2) 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)

xyzUiso*/UeqOcc. (<1)
O10.15396 (9)0.88990 (19)0.87624 (19)0.0181 (4)
O20.08897 (11)0.8780 (2)1.0641 (2)0.0208 (4)
N10.07470 (11)1.0610 (2)0.8828 (2)0.0164 (4)
H1N10.08411.07960.79460.020*
C1−0.00477 (14)1.1337 (3)1.0559 (3)0.0212 (5)
H1A−0.00061.04101.10250.025*
C2−0.04625 (16)1.2429 (3)1.1041 (3)0.0272 (6)
H2A−0.06971.22211.18340.033*
C3−0.05361 (16)1.3820 (3)1.0371 (4)0.0286 (6)
H3A−0.08101.45471.07160.034*
C4−0.01903 (15)1.4106 (3)0.9166 (3)0.0264 (6)
H4A−0.02441.50250.86840.032*
C50.02310 (14)1.3035 (3)0.8685 (3)0.0224 (5)
H5A0.04671.32460.78970.027*
C60.03042 (11)1.1636 (3)0.9376 (3)0.0155 (4)
C70.10429 (12)0.9363 (3)0.9525 (3)0.0165 (4)
C80.19360 (13)0.7514 (3)0.9145 (3)0.0180 (5)
C90.24506 (13)0.7554 (3)0.8015 (3)0.0161 (4)
H9A0.27830.83510.83980.019*0.55 (2)
H9B0.27360.84340.81630.019*0.45 (2)
C10A0.2126 (3)0.8036 (10)0.6393 (5)0.0169 (17)0.55 (2)
H10A0.17110.74350.60290.020*0.55 (2)
H10B0.19740.90620.64120.020*0.55 (2)
C10B0.2058 (3)0.7435 (16)0.6365 (7)0.025 (2)*0.45 (2)
H10C0.16530.80940.61890.030*0.45 (2)
H10D0.18950.64260.61360.030*0.45 (2)
C110.26080 (18)0.7903 (4)0.5329 (3)0.0338 (7)
H11A0.24760.83170.43650.041*0.55 (2)
H11B0.25060.86160.45210.041*0.45 (2)
C120.32574 (14)0.7183 (3)0.5690 (3)0.0205 (5)
C130.34562 (13)0.6355 (3)0.7083 (3)0.0227 (5)
H13A0.38670.68280.76870.027*
H13B0.35980.53690.68250.027*
C140.2908 (2)0.6188 (4)0.8067 (4)0.0392 (9)
H14A0.31410.60050.91100.047*
H14B0.26120.53360.77240.047*
C150.14268 (18)0.6215 (3)0.8893 (5)0.0355 (7)
H15A0.11250.62490.96290.053*
H15B0.16880.53010.90020.053*
H15C0.11460.62720.78870.053*
C160.23442 (17)0.7591 (4)1.0772 (3)0.0316 (7)
H16A0.20200.75631.14630.047*
H16B0.26100.84971.09150.047*
H16C0.26600.67601.09660.047*
C170.37752 (17)0.7262 (3)0.4634 (3)0.0271 (5)
H17A0.35780.78430.37570.041*
H17B0.38740.62780.43210.041*
H17C0.42040.77160.51510.041*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0224 (8)0.0176 (8)0.0163 (8)0.0042 (6)0.0091 (6)0.0011 (6)
O20.0282 (9)0.0201 (9)0.0167 (8)0.0026 (7)0.0113 (7)0.0013 (6)
N10.0198 (9)0.0193 (10)0.0116 (8)0.0022 (7)0.0069 (7)−0.0003 (7)
C10.0232 (11)0.0244 (13)0.0184 (11)0.0048 (9)0.0095 (9)0.0040 (9)
C20.0319 (14)0.0304 (15)0.0241 (12)0.0080 (10)0.0172 (11)0.0051 (10)
C30.0343 (14)0.0255 (14)0.0302 (14)0.0102 (11)0.0166 (12)0.0004 (10)
C40.0309 (13)0.0208 (12)0.0306 (14)0.0034 (10)0.0137 (11)0.0018 (10)
C50.0237 (11)0.0207 (13)0.0258 (12)0.0019 (9)0.0126 (9)0.0028 (9)
C60.0141 (9)0.0177 (11)0.0152 (9)−0.0004 (8)0.0042 (7)−0.0019 (8)
C70.0176 (10)0.0186 (11)0.0140 (10)−0.0009 (8)0.0051 (8)−0.0041 (8)
C80.0220 (11)0.0145 (11)0.0191 (11)0.0041 (8)0.0081 (8)0.0015 (8)
C90.0184 (9)0.0163 (11)0.0147 (10)0.0013 (8)0.0057 (8)−0.0006 (8)
C10A0.020 (2)0.018 (4)0.014 (2)0.0052 (19)0.0056 (14)0.0028 (15)
C110.0466 (17)0.0417 (17)0.0160 (12)0.0201 (14)0.0135 (12)0.0090 (11)
C120.0223 (11)0.0227 (12)0.0180 (10)0.0001 (9)0.0079 (9)−0.0042 (9)
C130.0210 (11)0.0260 (13)0.0227 (12)0.0058 (9)0.0079 (9)−0.0001 (9)
C140.0482 (17)0.0328 (16)0.0466 (19)0.0244 (14)0.0343 (16)0.0214 (14)
C150.0387 (15)0.0185 (13)0.057 (2)−0.0059 (11)0.0284 (15)−0.0076 (12)
C160.0340 (14)0.0489 (18)0.0134 (11)0.0186 (13)0.0082 (10)0.0086 (11)
C170.0346 (13)0.0235 (13)0.0273 (13)−0.0006 (10)0.0163 (11)−0.0031 (10)

Geometric parameters (Å, °)

O1—C71.345 (3)C10A—C111.458 (5)
O1—C81.470 (3)C10A—H10A0.9700
O2—C71.214 (3)C10A—H10B0.9700
N1—C71.356 (3)C10B—C111.594 (7)
N1—C61.409 (3)C10B—H10C0.9700
N1—H1N10.8600C10B—H10D0.9700
C1—C21.388 (4)C11—C121.393 (4)
C1—C61.389 (3)C11—H11A0.9300
C1—H1A0.9300C11—H11B0.9600
C2—C31.385 (4)C12—C131.441 (4)
C2—H2A0.9300C12—C171.502 (3)
C3—C41.396 (4)C13—C141.509 (4)
C3—H3A0.9300C13—H13A0.9700
C4—C51.383 (4)C13—H13B0.9700
C4—H4A0.9300C14—H14A0.9700
C5—C61.399 (4)C14—H14B0.9700
C5—H5A0.9300C15—H15A0.9600
C8—C151.517 (4)C15—H15B0.9600
C8—C161.520 (4)C15—H15C0.9600
C8—C91.547 (3)C16—H16A0.9600
C9—C141.510 (4)C16—H16B0.9600
C9—C10B1.531 (6)C16—H16C0.9600
C9—C10A1.531 (5)C17—H17A0.9600
C9—H9A0.9800C17—H17B0.9600
C9—H9B0.9600C17—H17C0.9600
C7—O1—C8122.38 (19)H10A—C10A—H10B107.7
C7—N1—C6127.81 (19)C9—C10B—C11106.2 (5)
C7—N1—H1N1116.1C9—C10B—H10C110.5
C6—N1—H1N1116.1C11—C10B—H10C110.5
C2—C1—C6119.6 (2)C9—C10B—H10D110.5
C2—C1—H1A120.2C11—C10B—H10D110.5
C6—C1—H1A120.2H10C—C10B—H10D108.7
C3—C2—C1121.6 (3)C12—C11—C10A123.1 (3)
C3—C2—H2A119.2C12—C11—C10B114.4 (4)
C1—C2—H2A119.2C12—C11—H11A118.5
C2—C3—C4118.5 (3)C10A—C11—H11A118.5
C2—C3—H3A120.8C10B—C11—H11A123.4
C4—C3—H3A120.8C12—C11—H11B122.2
C5—C4—C3120.5 (3)C10A—C11—H11B111.8
C5—C4—H4A119.7C10B—C11—H11B123.4
C3—C4—H4A119.7C11—C12—C13121.4 (2)
C4—C5—C6120.4 (2)C11—C12—C17120.6 (2)
C4—C5—H5A119.8C13—C12—C17118.0 (2)
C6—C5—H5A119.8C12—C13—C14117.1 (2)
C1—C6—C5119.3 (2)C12—C13—H13A108.0
C1—C6—N1123.8 (2)C14—C13—H13A108.0
C5—C6—N1117.0 (2)C12—C13—H13B108.0
O2—C7—O1126.3 (2)C14—C13—H13B108.0
O2—C7—N1126.1 (2)H13A—C13—H13B107.3
O1—C7—N1107.62 (19)C13—C14—C9111.8 (2)
O1—C8—C15109.0 (2)C13—C14—H14A109.3
O1—C8—C16109.7 (2)C9—C14—H14A109.3
C15—C8—C16112.4 (3)C13—C14—H14B109.3
O1—C8—C9101.42 (18)C9—C14—H14B109.3
C15—C8—C9113.5 (2)H14A—C14—H14B107.9
C16—C8—C9110.2 (2)C8—C15—H15A109.5
C14—C9—C10B98.7 (5)C8—C15—H15B109.5
C14—C9—C10A113.1 (3)H15A—C15—H15B109.5
C14—C9—C8113.9 (2)C8—C15—H15C109.5
C10B—C9—C8111.6 (3)H15A—C15—H15C109.5
C10A—C9—C8115.4 (2)H15B—C15—H15C109.5
C14—C9—H9A104.3C8—C16—H16A109.5
C10B—C9—H9A124.1C8—C16—H16B109.5
C10A—C9—H9A104.3H16A—C16—H16B109.5
C8—C9—H9A104.3C8—C16—H16C109.5
C14—C9—H9B110.6H16A—C16—H16C109.5
C10B—C9—H9B111.0H16B—C16—H16C109.5
C10A—C9—H9B91.0C12—C17—H17A109.5
C8—C9—H9B110.7C12—C17—H17B109.5
C11—C10A—C9113.5 (3)H17A—C17—H17B109.5
C11—C10A—H10A108.9C12—C17—H17C109.5
C9—C10A—H10A108.9H17A—C17—H17C109.5
C11—C10A—H10B108.9H17B—C17—H17C109.5
C9—C10A—H10B108.9
C6—C1—C2—C30.0 (5)O1—C8—C9—C10A−43.0 (5)
C1—C2—C3—C41.0 (5)C15—C8—C9—C10A73.8 (5)
C2—C3—C4—C5−1.7 (5)C16—C8—C9—C10A−159.1 (4)
C3—C4—C5—C61.4 (5)C14—C9—C10A—C11−40.1 (8)
C2—C1—C6—C5−0.3 (4)C10B—C9—C10A—C11−89.5 (9)
C2—C1—C6—N1178.8 (2)C8—C9—C10A—C11−173.6 (5)
C4—C5—C6—C1−0.4 (4)C14—C9—C10B—C11−74.1 (7)
C4—C5—C6—N1−179.5 (2)C10A—C9—C10B—C1160.9 (8)
C7—N1—C6—C1−17.3 (4)C8—C9—C10B—C11165.8 (5)
C7—N1—C6—C5161.8 (2)C9—C10A—C11—C129.9 (9)
C8—O1—C7—O24.6 (4)C9—C10A—C11—C10B80.2 (9)
C8—O1—C7—N1−175.8 (2)C9—C10B—C11—C1249.7 (9)
C6—N1—C7—O212.6 (4)C9—C10B—C11—C10A−70.3 (9)
C6—N1—C7—O1−166.9 (2)C10A—C11—C12—C138.1 (7)
C7—O1—C8—C1562.9 (3)C10B—C11—C12—C13−13.0 (6)
C7—O1—C8—C16−60.6 (3)C10A—C11—C12—C17−171.4 (5)
C7—O1—C8—C9−177.0 (2)C10B—C11—C12—C17167.5 (5)
O1—C8—C9—C14−176.2 (3)C11—C12—C13—C145.2 (4)
C15—C8—C9—C14−59.4 (3)C17—C12—C13—C14−175.3 (3)
C16—C8—C9—C1467.7 (3)C12—C13—C14—C9−35.1 (4)
O1—C8—C9—C10B−65.4 (6)C10B—C9—C14—C1368.3 (5)
C15—C8—C9—C10B51.3 (6)C10A—C9—C14—C1352.4 (5)
C16—C8—C9—C10B178.4 (6)C8—C9—C14—C13−173.4 (3)

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of C1–C6 phenyl ring.
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O2i0.862.122.969 (3)170
C13—H13A···Cg1ii0.972.623.566 (3)166

Symmetry codes: (i) x, −y+2, z−1/2; (ii) x+1/2, y−1/2, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB5524).

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