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Crystal structures of methyl 3-phenyl-4,5-di­hydro-1H,3H-benzo[4,5]imidazo[2,1-c][1,4]oxazepine-4-carboxyl­ate and methyl 1-methyl-3-phenyl-4,5-di­hydro-1H,3H-benzo[4,5]imidazo[2,1-c][1,4]oxazepine-4-carboxyl­ate

aDepartment of Physics, Pachaiyappa's College for Men, Kanchipuram 631 501, India, bDepartment of Physics, Presidency College (Autonomous), Chennai 600 005, India, and cDepartment of Organic Chemistry, University of Madras, Guindy campus, Chennai 602 025, India
*Correspondence e-mail: aspandian59@gmail.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 19 September 2014; accepted 1 October 2014; online 8 October 2014)

The title compounds, C19H18N2O3, (I), and C20H20N2O3, (II), differ only by a methyl substituent on the seven-membered oxazepine ring in (II). In both compounds, these rings have a twist-chair conformation. The phenyl ring makes a dihedral angle of 73.42 (10)° with the benzimidazole ring system mean plane (r.m.s. deviation = 0.015 Å) in (I) and 83.07 (7)° in (II) (r.m.s. deviation = 0.026 Å). The methyl carboxyl­ate groups are planar to within 0.031 (2) in (I) and 0.003 (2) Å in (II). They are inclined to the phenyl and benzimidazole ring system by 33.78 (16) and 87.56 (14)°, respectively, in (I) and by 53.04 (12) and 60.22 (11)°, respectively, in (II). In the crystal of (I), mol­ecules stack in a herringbone fashion and are linked by C—H⋯O hydrogen bonds, forming chains along [100]. In the crystal of (II), there are no significant inter­molecular inter­actions present.

1. Chemical context

Fused oxazepinone derivatives have attracted considerable attention owing to their promising biological activities, such as anti­cancer, anti-HIV, anti­depressant and anti­tumor activities (Liu et al., 2011[Liu, Y., Chu, C., Huang, A., Zhan, C. & Ma, C. (2011). ACS Comb. Sci. 13, 547-553.]). Tumor growth requires the support of an associated blood supply, making tumor vasculature a potential target for anti­cancer therapy. This principle has inspired decades of research into the pathways of angiogenesis (the formation of new blood vessels), leading to the identification of a family of vascular endothelial growth factors (VEGFs) that stimulate this process (Edwards et al., 2011[Edwards, D. J., Hadfield, J. A., Wallace, T. W. & Ducki, S. (2011). Org. Biomol. Chem. 9, 219-231.]). Seven-membered oxygen heterocycles are ubiquitous in natural products and show a wide spectrum of biological activity (Bera et al., 2014[Bera, K., Jalal, S., Sarkar, S. & Jana, U. (2014). Org. Biomol. Chem. 12, 57-61.]).

[Scheme 1]

2. Structural commentary

The mol­ecular structure of compound (I)[link] is illustrated in Fig. 1[link]. The C1—N1—C13 bond angle is 105.2 (2)°. The seven-membered oxazepine ring (O1/N2/C7/C8/C11–C13) has a twist-chair conformation, as can be evidenced by the torsion angles C12—C13—N2—C7 = −3.2 (3) and C8—C11—O1—C12 = −78.33 (18)°. The phenyl ring (C14–C19) is inclined to the benzimidazole ring system [N1/N2/C1–C6/C13; r.m.s. deviation = 0.026 Å] by 73.42 (10)°. The methyl carboxyl­ate group (C9/O2/O3/C10) is planar to within 0.031 (2) Å and is inclined to the phenyl ring and the benzimidazole ring system by 33.78 (16) and 87.56 (14)°, respectively.

[Figure 1]
Figure 1
The mol­ecular structure of compound (I)[link], with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.

The mol­ecular structure of compound (II)[link] is illustrated in Fig. 2[link]. The C1—N1—C13 bond angle of 104.27 (15)°. The seven-membered oxazepine ring (O1/N2/C7/C8/C11–C13) also has a twist-chair conformation, with torsion angles C12—C13—N2—C7 = −6.6 (3) and C8—C11—O1—C12 = −74.17 (18)°.

[Figure 2]
Figure 2
The mol­ecular structure of compound (II)[link], with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.

The principle difference in the two compounds concerns the orientation of the phenyl ring (C15–C20) with respect to the benzimidazole ring system [N1/N2/C1–C6/C13; r.m.s. deviation = 0.026 Å]. In (II)[link], this angle is 83.07 (17)° considerably larger than the same angle in (I)[link], viz 73.42 (10)°. Here the methyl carboxyl­ate group (C9/O2/O3/C10), planar to within 0.003 (2) Å, is inclined to the phenyl ring and the benzimid­azole ring system by 53.04 (12) and 60.22 (11)°, respectively. These angles are also very different to those observed in compound (I)[link], viz 33.78 (16) and 87.56 (14)°, respectively.

3. Supra­molecular features

In the crystal of (I)[link], mol­ecules stack in a herringbone fashion and are linked by C—H⋯O hydrogen bonds, forming chains along the a-axis direction (Table 1[link] and Fig. 3[link]).

Table 1
Hydrogen-bond geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8⋯O2i 0.98 2.35 3.225 (2) 148
Symmetry code: (i) [x-{\script{1\over 2}}, -y, z].
[Figure 3]
Figure 3
A view along the b axis of the crystal packing of compound (I)[link]. The hydrogen bonds are shown as dashed lines (see Table 1[link] for details).

In the crystal of (II)[link], there are no significant inter­molecular inter­actions present.

4. Database survey

In the Cambridge Structural Database (Version 5.35, last update May 2014; Groom & Allen, 2014[Groom, C. R. & Allen, F. H. (2014). Angew. Chem. Int. Ed. Engl. 53, 662-671.]) there are a large number of compounds containing an oxazepine-type ring, but only one entry was found for such a ring fused to a benz­imid­azole unit. This compound, 1H,3H-[1,4][4,3-a]benzimid­azole (UQILOW; Zhang et al., 2011[Zhang, X., Zhou, Y., Wang, H., Guo, D., Ye, D., Xu, Y., Jiang, H. & Liu, H. (2011). Green Chem. 13, 397-405.]), has an oxazepino ring with a C=C bond in the seven-membered ring.

5. Synthesis and crystallization

A mixture of Z-methyl-2-(bromo­meth­yl)-3-phenyl­acrylate (1.0 mol) and (1H-benzo[d]imidazole-2-yl)methanol (1.1 mol) for (I)[link], but (1H-benzo[d]imidazole-2-yl)ethanol (1.1 mol) for (II)[link], together with CS2CO3 (1 mol) in CH3CN (10 ml) was stirred for 8 h. After completion of the reactions, monitored by TLC, the solvents were evaporated under reduced pressure. The residues were diluted with ethyl acetate then washed with brine and water. The organic layers were separated and the residues were subjected to column chromatography using ethyl acetate and hexane (2:8) as eluent. The products were dissolved in chloro­form and heated for 2 min. The resulting solutions were subjected to crystallization by slow evaporation of the solvent for 48 h resulting in the formation of colourless block-like crystals of compounds (I)[link] and (II)[link].

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

  (I) (II)
Crystal data
Chemical formula C19H18N2O3 C20H20N2O3
Mr 322.35 336.38
Crystal system, space group Orthorhombic, Pca21 Orthorhombic, P212121
Temperature (K) 293 293
a, b, c (Å) 9.9238 (13), 7.3322 (10), 23.028 (3) 9.1115 (7), 9.6470 (8), 19.4856 (15)
V3) 1675.6 (4) 1712.8 (2)
Z 4 4
Radiation type Mo Kα Mo Kα
μ (mm−1) 0.09 0.09
Crystal size (mm) 0.21 × 0.19 × 0.18 0.21 × 0.19 × 0.18
 
Data collection
Diffractometer Bruker SMART APEXII CCD Bruker SMART APEXII CCD
Absorption correction Multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.982, 0.984 0.981, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections 15223, 3639, 2782 30423, 3847, 2958
Rint 0.023 0.043
(sin θ/λ)max−1) 0.637 0.645
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.089, 1.04 0.037, 0.089, 1.06
No. of reflections 3587 3844
No. of parameters 217 226
No. of restraints 1 0
H-atom treatment H-atom parameters constrained H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.13, −0.13 0.15, −0.13
Computer programs: APEX2 and SAINT (Bruker, 2008[Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS97 and SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

In both compunds, the C-bound H atoms were positioned geometrically and allowed to ride on their parent atoms: C—H = 0.93–0.98 Å with Uiso(H) = .2Ueq(C) or 1.5Ueq(Cmethyl).

Supporting information


Chemical context top

Fused oxazepinone derivatives have attracted considerable attention owing to their promising biological activities, such as anti­cancer, anti-HIV, anti­depressant and anti­tumor activities (Liu et al., 2011). Tumor growth requires the support of an associated blood supply, making tumor vasculature a potential target for anti­cancer therapy. This principle has inspired decades of research into the pathways of angiogenesis (the formation of new blood vessels), leading to the identification of a family of vascular endothelial growth factors (VEGFs) that stimulate this process (Edwards et al., 2011). Seven-membered oxygen heterocycles are ubiquitous in natural products and show a wide spectrum of biological activity (Bera et al., 2014).

Structural commentary top

The molecular structure of compound (I) is illustrated in Fig. 1. The C1—N1—C13 bond angle is 105.2 (2) ° indicating sp2 hybridization for atom N1. The seven-membered oxazepine ring (O1/N2/C7/C8/C11–C13) has a twist-chair conformation, as can be evidenced by the torsion angles C12—C13—N2—C7 = -3.2 (3)° and C8—C11—O1—C12 = -78.33 (18)°. The phenyl ring (C14–C19) is inclined to the benzimidazole ring system [N1/N2/C1–C6/C13; r.m.s. deviation = 0.026 Å] by 73.42 (10)°. The methyl carboxyl­ate group (C9/O2/O3/C10) is planar to within 0.031 (2) Å and is inclined to the phenyl ring and the benzimidazole ring system by 33.78 (16) and 87.56 (14)°, respectively.

The molecular structure of compound (II) is illustrated in Fig. 2. As in compound (I) the sp2 hybridization of atom N1 is confirmed by the C1—N1—C13 bond angle of 104.27 (15)°. The seven-membered oxazepine ring (O1/N2/C7/C8/C11–C13) also has a twist-chair conformation, with torsion angles C12—C13—N2—C7 = -6.6 (3) and C8—C11—O1—C12 = -74.17 (18)°.

The principle difference in the two compounds concerns the orientation of the phenyl ring (C15–C20) with respect to the benzimidazole ring system [N1/N2/C1–C6/C13; r.m.s. deviation = 0.026 Å]. In (II), this angle is 83.07 (17)° considerably larger than the same angle in (I), viz 73.42 (10)°. Here the methyl carboxyl­ate group (C9/O2/O3/C10), planar to within 0.003 (2) Å, is inclined to the phenyl ring and the benzimidazole ring system by 53.04 (12) and 60.22 (11)°, respectively. These angles are also very different to those observed in compound (I), viz 33.78 (16) and 87.56 (14)°, respectively.

Supra­molecular features top

In the crystal of (I), molecules stack in a herringbone fashion and are linked by C—H···O hydrogen bonds, forming chains along the a-axis direction (Table 1 and Fig. 3).

In the crystal of (II), there are no significant inter­molecular inter­actions present.

Database survey top

In the Cambridge Structural Database (Version 5.35, last update May 2014; Groom & Allen, 2014) there are a large number of compounds containing an oxazepine-type ring, but only one entry was found for such a ring fused to a benzimidazole unit. This compound, 1H,3H-[1,4]Dear Matthias,[4,3-a]benzimidazole (UQILOW; Zhang et al., 2011), has an oxazepino ring with a CC bond in the seven-membered ring.

Synthesis and crystallization top

A mixture of Z-methyl-2-(bromo­methyl)-3-phenyl­acrylate (1.0 mol) and (1H-benzo[d]imidazole-2-yl)methanol (1.1 mol) for (I), but (1H-benzo[d]imidazole-2-yl)ethanol (1.1 mol) for (II), together with CS2CO3 (1 mol) in CH3CN (10 ml) was stirred for 8 h. After completion of the reactions, monitored by TLC, the solvents were evaporated under reduced pressure. The residues were diluted with ethyl acetate then washed with brine and water. The organic layers were separated and the residues were subjected to column chromatography using ethyl acetate and hexane (2:8) as eluent. The products were dissolved in chloro­form and heated for 2 min. The resulting solutions were subjected to crystallization by slow evaporation of the solvent for 48 h resulting in the formation of colourless block-like crystals of compounds (I) and (II).

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 2. For both compounds, the C-bound H atoms were positioned geometrically and allowed to ride on their parent atoms: C—H = 0.93–0.98 Å with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for other H atoms.

Related literature top

For related literature, Bera et al. (2014); Edwards et al. (2011); Liu et al. (2011); Zhang et al. (2011).

Computing details top

For both compounds, data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
The molecular structure of compound (I), with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.

The molecular structure of compound (II), with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.

A view along the b axis of the crystal packing of compound (I). The hydrogen bonds are shown as dashed lines (see Table 1 for details).
(I) Methyl 3-phenyl-1,3,4,5-tetrahydro-2-benzoxepine-4-carboxylate top
Crystal data top
C19H18N2O3F(000) = 680
Mr = 322.35Dx = 1.278 Mg m3
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2acCell parameters from 2782 reflections
a = 9.9238 (13) Åθ = 2.8–26.9°
b = 7.3322 (10) ŵ = 0.09 mm1
c = 23.028 (3) ÅT = 293 K
V = 1675.6 (4) Å3Block, colourless
Z = 40.21 × 0.19 × 0.18 mm
Data collection top
Bruker SMART APEXII CCD
diffractometer
3639 independent reflections
Radiation source: fine-focus sealed tube2782 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
ω and ϕ scansθmax = 26.9°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1212
Tmin = 0.982, Tmax = 0.984k = 89
15223 measured reflectionsl = 2929
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.089H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.036P)2 + 0.2289P]
where P = (Fo2 + 2Fc2)/3
3587 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 0.13 e Å3
1 restraintΔρmin = 0.13 e Å3
Crystal data top
C19H18N2O3V = 1675.6 (4) Å3
Mr = 322.35Z = 4
Orthorhombic, Pca21Mo Kα radiation
a = 9.9238 (13) ŵ = 0.09 mm1
b = 7.3322 (10) ÅT = 293 K
c = 23.028 (3) Å0.21 × 0.19 × 0.18 mm
Data collection top
Bruker SMART APEXII CCD
diffractometer
3639 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2782 reflections with I > 2σ(I)
Tmin = 0.982, Tmax = 0.984Rint = 0.023
15223 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0361 restraint
wR(F2) = 0.089H-atom parameters constrained
S = 1.04Δρmax = 0.13 e Å3
3587 reflectionsΔρmin = 0.13 e Å3
217 parameters
Special details top

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 F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(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) top
xyzUiso*/Ueq
C10.4382 (2)0.3837 (4)0.11593 (9)0.0668 (6)
C20.3291 (3)0.3704 (5)0.07782 (11)0.0965 (11)
H20.27520.47110.06980.116*
C30.3040 (3)0.2059 (7)0.05276 (12)0.1077 (13)
H30.23300.19560.02660.129*
C40.3806 (3)0.0547 (5)0.06498 (11)0.0949 (10)
H40.35960.05520.04700.114*
C50.4883 (3)0.0607 (4)0.10335 (9)0.0729 (7)
H50.53950.04210.11200.088*
C60.51486 (19)0.2287 (3)0.12797 (8)0.0565 (5)
C70.71826 (18)0.1761 (3)0.19213 (8)0.0494 (5)
H7A0.80390.22270.17830.059*
H7B0.70910.05180.17830.059*
C80.71913 (16)0.1753 (2)0.25811 (8)0.0414 (4)
H80.62790.14960.27220.050*
C90.81229 (19)0.0262 (3)0.27800 (11)0.0543 (5)
C100.8540 (3)0.1888 (3)0.35086 (17)0.1108 (12)
H10A0.80940.24790.38270.166*
H10B0.93080.12290.36500.166*
H10C0.88290.27870.32330.166*
C110.76835 (17)0.3568 (2)0.28451 (8)0.0426 (4)
H110.85160.39340.26480.051*
C120.6665 (2)0.5738 (3)0.21970 (8)0.0569 (5)
H12A0.75800.58380.20520.068*
H12B0.62940.69590.22210.068*
C130.5859 (2)0.4662 (3)0.17812 (8)0.0529 (5)
C140.79603 (19)0.3405 (2)0.34844 (9)0.0451 (4)
C150.9245 (2)0.3012 (3)0.36803 (9)0.0599 (5)
H150.99540.29060.34180.072*
C160.9471 (3)0.2780 (4)0.42653 (11)0.0803 (7)
H161.03340.25010.43940.096*
C170.8469 (3)0.2949 (4)0.46535 (12)0.0863 (8)
H170.86440.27910.50470.104*
C180.7184 (3)0.3354 (4)0.44701 (11)0.0790 (7)
H180.64910.34770.47390.095*
C190.6932 (2)0.3577 (3)0.38873 (9)0.0584 (5)
H190.60630.38450.37630.070*
N10.4836 (2)0.5295 (3)0.14829 (7)0.0704 (6)
N20.61033 (15)0.2858 (2)0.16772 (7)0.0495 (4)
O10.66982 (12)0.49625 (16)0.27650 (5)0.0493 (3)
O20.92024 (16)0.0028 (3)0.25663 (8)0.0875 (6)
O30.76188 (15)0.06347 (19)0.32311 (8)0.0731 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0537 (11)0.113 (2)0.0338 (10)0.0156 (13)0.0052 (10)0.0122 (12)
C20.0676 (16)0.179 (3)0.0431 (13)0.0294 (19)0.0003 (12)0.0169 (18)
C30.0673 (18)0.214 (4)0.0416 (14)0.009 (2)0.0098 (12)0.008 (2)
C40.0818 (18)0.154 (3)0.0486 (14)0.038 (2)0.0044 (14)0.0103 (17)
C50.0713 (14)0.101 (2)0.0468 (12)0.0204 (14)0.0004 (10)0.0019 (12)
C60.0467 (10)0.0880 (16)0.0348 (9)0.0028 (11)0.0047 (8)0.0045 (10)
C70.0430 (10)0.0484 (11)0.0569 (12)0.0063 (8)0.0022 (9)0.0057 (9)
C80.0315 (8)0.0407 (9)0.0520 (11)0.0019 (7)0.0012 (8)0.0017 (8)
C90.0509 (11)0.0426 (11)0.0694 (13)0.0080 (9)0.0161 (11)0.0093 (11)
C100.125 (2)0.0531 (15)0.154 (3)0.0007 (15)0.064 (2)0.0333 (17)
C110.0382 (9)0.0372 (9)0.0523 (11)0.0003 (7)0.0047 (8)0.0020 (8)
C120.0711 (13)0.0446 (11)0.0549 (12)0.0122 (9)0.0081 (10)0.0090 (10)
C130.0549 (11)0.0600 (13)0.0438 (10)0.0164 (10)0.0099 (9)0.0085 (9)
C140.0511 (11)0.0342 (9)0.0499 (10)0.0061 (8)0.0018 (9)0.0030 (8)
C150.0531 (12)0.0653 (13)0.0613 (12)0.0099 (10)0.0080 (10)0.0026 (11)
C160.0722 (16)0.0975 (19)0.0713 (17)0.0075 (15)0.0227 (14)0.0070 (14)
C170.108 (2)0.099 (2)0.0517 (13)0.0040 (17)0.0174 (15)0.0100 (14)
C180.0915 (18)0.0936 (19)0.0520 (13)0.0024 (15)0.0063 (13)0.0069 (13)
C190.0614 (12)0.0608 (13)0.0529 (12)0.0035 (10)0.0024 (10)0.0040 (10)
N10.0707 (12)0.0952 (15)0.0453 (9)0.0331 (11)0.0072 (9)0.0167 (11)
N20.0443 (8)0.0604 (10)0.0439 (8)0.0048 (7)0.0012 (7)0.0036 (8)
O10.0583 (7)0.0422 (7)0.0473 (7)0.0116 (6)0.0064 (6)0.0032 (6)
O20.0660 (9)0.1071 (14)0.0894 (12)0.0453 (9)0.0061 (9)0.0073 (10)
O30.0724 (9)0.0452 (8)0.1017 (13)0.0065 (7)0.0233 (9)0.0245 (8)
Geometric parameters (Å, º) top
C1—N11.379 (3)C10—H10B0.9600
C1—C61.395 (3)C10—H10C0.9600
C1—C21.397 (3)C11—O11.427 (2)
C2—C31.360 (5)C11—C141.502 (3)
C2—H20.9300C11—H110.9800
C3—C41.374 (5)C12—O11.427 (2)
C3—H30.9300C12—C131.476 (3)
C4—C51.387 (4)C12—H12A0.9700
C4—H40.9300C12—H12B0.9700
C5—C61.382 (3)C13—N11.311 (3)
C5—H50.9300C13—N21.366 (2)
C6—N21.382 (3)C14—C151.383 (3)
C7—N21.452 (2)C14—C191.385 (3)
C7—C81.519 (3)C15—C161.376 (3)
C7—H7A0.9700C15—H150.9300
C7—H7B0.9700C16—C171.343 (4)
C8—C91.503 (3)C16—H160.9300
C8—C111.543 (2)C17—C181.375 (4)
C8—H80.9800C17—H170.9300
C9—O21.198 (2)C18—C191.375 (3)
C9—O31.327 (3)C18—H180.9300
C10—O31.445 (3)C19—H190.9300
C10—H10A0.9600
N1—C1—C6110.23 (18)O1—C11—C14108.00 (14)
N1—C1—C2130.3 (3)O1—C11—C8110.51 (13)
C6—C1—C2119.4 (3)C14—C11—C8112.06 (14)
C3—C2—C1118.0 (3)O1—C11—H11108.7
C3—C2—H2121.0C14—C11—H11108.7
C1—C2—H2121.0C8—C11—H11108.7
C2—C3—C4121.8 (3)O1—C12—C13113.21 (16)
C2—C3—H3119.1O1—C12—H12A108.9
C4—C3—H3119.1C13—C12—H12A108.9
C3—C4—C5122.1 (3)O1—C12—H12B108.9
C3—C4—H4119.0C13—C12—H12B108.9
C5—C4—H4119.0H12A—C12—H12B107.7
C6—C5—C4115.9 (3)N1—C13—N2112.87 (19)
C6—C5—H5122.1N1—C13—C12124.78 (19)
C4—C5—H5122.1N2—C13—C12122.34 (17)
C5—C6—N2132.3 (2)C15—C14—C19118.68 (18)
C5—C6—C1122.7 (2)C15—C14—C11120.32 (18)
N2—C6—C1105.0 (2)C19—C14—C11120.95 (16)
N2—C7—C8113.17 (15)C16—C15—C14119.7 (2)
N2—C7—H7A108.9C16—C15—H15120.2
C8—C7—H7A108.9C14—C15—H15120.2
N2—C7—H7B108.9C17—C16—C15121.3 (2)
C8—C7—H7B108.9C17—C16—H16119.3
H7A—C7—H7B107.8C15—C16—H16119.3
C9—C8—C7108.13 (15)C16—C17—C18120.1 (2)
C9—C8—C11108.21 (13)C16—C17—H17119.9
C7—C8—C11113.10 (15)C18—C17—H17119.9
C9—C8—H8109.1C19—C18—C17119.6 (2)
C7—C8—H8109.1C19—C18—H18120.2
C11—C8—H8109.1C17—C18—H18120.2
O2—C9—O3124.79 (19)C18—C19—C14120.6 (2)
O2—C9—C8123.6 (2)C18—C19—H19119.7
O3—C9—C8111.53 (17)C14—C19—H19119.7
O3—C10—H10A109.5C13—N1—C1105.17 (18)
O3—C10—H10B109.5C13—N2—C6106.70 (17)
H10A—C10—H10B109.5C13—N2—C7126.82 (17)
O3—C10—H10C109.5C6—N2—C7126.45 (17)
H10A—C10—H10C109.5C12—O1—C11114.83 (14)
H10B—C10—H10C109.5C9—O3—C10115.0 (2)
N1—C1—C2—C3177.7 (3)C19—C14—C15—C160.8 (3)
C6—C1—C2—C31.5 (3)C11—C14—C15—C16176.87 (19)
C1—C2—C3—C41.4 (4)C14—C15—C16—C170.8 (4)
C2—C3—C4—C50.3 (4)C15—C16—C17—C180.2 (4)
C3—C4—C5—C60.8 (4)C16—C17—C18—C190.3 (4)
C4—C5—C6—N2179.0 (2)C17—C18—C19—C140.3 (4)
C4—C5—C6—C10.7 (3)C15—C14—C19—C180.3 (3)
N1—C1—C6—C5177.41 (19)C11—C14—C19—C18177.4 (2)
C2—C1—C6—C50.5 (3)N2—C13—N1—C10.5 (2)
N1—C1—C6—N21.3 (2)C12—C13—N1—C1179.41 (18)
C2—C1—C6—N2178.24 (18)C6—C1—N1—C131.1 (2)
N2—C7—C8—C9167.11 (15)C2—C1—N1—C13177.6 (2)
N2—C7—C8—C1173.09 (19)N1—C13—N2—C60.3 (2)
C7—C8—C9—O243.1 (2)C12—C13—N2—C6178.63 (16)
C11—C8—C9—O279.7 (2)N1—C13—N2—C7177.88 (17)
C7—C8—C9—O3139.11 (17)C12—C13—N2—C73.2 (3)
C11—C8—C9—O398.05 (18)C5—C6—N2—C13177.6 (2)
C9—C8—C11—O1168.75 (16)C1—C6—N2—C131.0 (2)
C7—C8—C11—O171.48 (17)C5—C6—N2—C74.2 (3)
C9—C8—C11—C1448.3 (2)C1—C6—N2—C7177.23 (17)
C7—C8—C11—C14168.02 (15)C8—C7—N2—C1356.5 (2)
O1—C12—C13—N1123.32 (19)C8—C7—N2—C6125.66 (19)
O1—C12—C13—N255.5 (2)C13—C12—O1—C1183.6 (2)
O1—C11—C14—C15144.36 (17)C14—C11—O1—C12158.78 (15)
C8—C11—C14—C1593.7 (2)C8—C11—O1—C1278.33 (18)
O1—C11—C14—C1938.0 (2)O2—C9—O3—C107.4 (3)
C8—C11—C14—C1983.9 (2)C8—C9—O3—C10170.35 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O2i0.982.353.225 (2)148
Symmetry code: (i) x1/2, y, z.
(II) Methyl 1-methyl-3-phenyl-4,5-dihydro-1H,3H-benzo[4,5]imidazo[2,1-c][1,4]oxazepine-4-carboxylate top
Crystal data top
C20H20N2O3F(000) = 712
Mr = 336.38Dx = 1.304 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 2958 reflections
a = 9.1115 (7) Åθ = 2.1–27.3°
b = 9.6470 (8) ŵ = 0.09 mm1
c = 19.4856 (15) ÅT = 293 K
V = 1712.8 (2) Å3Block, colourless
Z = 40.21 × 0.19 × 0.18 mm
Data collection top
Bruker SMART APEXII CCD
diffractometer
3847 independent reflections
Radiation source: fine-focus sealed tube2958 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.043
ω and ϕ scansθmax = 27.3°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1111
Tmin = 0.981, Tmax = 0.984k = 1212
30423 measured reflectionsl = 2525
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.089H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0335P)2 + 0.3064P]
where P = (Fo2 + 2Fc2)/3
3844 reflections(Δ/σ)max < 0.001
226 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = 0.13 e Å3
Crystal data top
C20H20N2O3V = 1712.8 (2) Å3
Mr = 336.38Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.1115 (7) ŵ = 0.09 mm1
b = 9.6470 (8) ÅT = 293 K
c = 19.4856 (15) Å0.21 × 0.19 × 0.18 mm
Data collection top
Bruker SMART APEXII CCD
diffractometer
3847 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2958 reflections with I > 2σ(I)
Tmin = 0.981, Tmax = 0.984Rint = 0.043
30423 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.089H-atom parameters constrained
S = 1.06Δρmax = 0.15 e Å3
3844 reflectionsΔρmin = 0.13 e Å3
226 parameters
Special details top

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 F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(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) top
xyzUiso*/Ueq
C10.43553 (19)0.09161 (19)0.06180 (9)0.0410 (4)
C20.4623 (2)0.1711 (2)0.11986 (9)0.0490 (5)
H20.52900.14220.15300.059*
C30.3875 (2)0.2934 (2)0.12673 (10)0.0525 (5)
H30.40440.34830.16520.063*
C40.2871 (2)0.3375 (2)0.07775 (10)0.0541 (5)
H40.23900.42160.08400.065*
C50.2572 (2)0.2600 (2)0.02042 (10)0.0501 (5)
H50.18930.28890.01220.060*
C60.33290 (19)0.13700 (19)0.01370 (9)0.0411 (4)
C70.2428 (2)0.0325 (2)0.09788 (9)0.0471 (4)
H7A0.18880.05410.09830.057*
H7B0.17190.10740.09580.057*
C80.32954 (19)0.04495 (18)0.16429 (8)0.0368 (4)
H80.39380.12620.16140.044*
C90.21833 (18)0.06790 (19)0.22047 (9)0.0393 (4)
C100.1375 (3)0.2192 (3)0.30710 (11)0.0694 (7)
H10A0.16430.30630.32740.104*
H10B0.13940.14810.34150.104*
H10C0.04040.22590.28820.104*
C110.42285 (19)0.08308 (18)0.18173 (9)0.0394 (4)
H110.35800.16340.18710.047*
C120.4747 (2)0.17200 (19)0.06734 (9)0.0487 (5)
H120.38660.22680.07710.058*
C130.4367 (2)0.05805 (18)0.01878 (9)0.0429 (4)
C140.5926 (3)0.2654 (2)0.03933 (12)0.0712 (7)
H14A0.61380.33700.07210.107*
H14B0.67970.21220.03080.107*
H14C0.55940.30660.00270.107*
C150.50539 (18)0.06069 (16)0.24765 (10)0.0379 (4)
C160.4532 (2)0.11214 (19)0.30893 (9)0.0465 (4)
H160.36620.16260.30980.056*
C170.5294 (2)0.0891 (2)0.36909 (10)0.0552 (5)
H170.49280.12370.41020.066*
C180.6573 (2)0.0165 (2)0.36889 (11)0.0566 (5)
H180.70870.00250.40950.068*
C190.7098 (2)0.0359 (2)0.30812 (11)0.0552 (5)
H190.79690.08610.30760.066*
C200.63416 (19)0.01449 (19)0.24811 (11)0.0488 (4)
H200.67020.05110.20730.059*
N10.50049 (16)0.03094 (16)0.04017 (7)0.0458 (4)
N20.33366 (16)0.03703 (16)0.03703 (7)0.0447 (4)
O10.52857 (14)0.11254 (12)0.12973 (6)0.0446 (3)
O20.11936 (15)0.01004 (15)0.23210 (7)0.0603 (4)
O30.23993 (15)0.18523 (13)0.25338 (7)0.0535 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0375 (9)0.0489 (10)0.0367 (9)0.0039 (8)0.0027 (8)0.0057 (8)
C20.0386 (9)0.0684 (13)0.0399 (10)0.0008 (10)0.0022 (8)0.0003 (9)
C30.0456 (11)0.0683 (14)0.0435 (11)0.0030 (10)0.0077 (9)0.0088 (10)
C40.0544 (12)0.0584 (12)0.0494 (12)0.0093 (10)0.0118 (10)0.0019 (10)
C50.0489 (11)0.0634 (12)0.0381 (10)0.0133 (10)0.0035 (9)0.0053 (10)
C60.0379 (9)0.0524 (10)0.0330 (9)0.0016 (8)0.0053 (8)0.0036 (8)
C70.0405 (9)0.0627 (12)0.0381 (10)0.0040 (9)0.0042 (8)0.0007 (9)
C80.0354 (9)0.0372 (9)0.0379 (9)0.0036 (7)0.0033 (7)0.0022 (8)
C90.0378 (9)0.0434 (10)0.0368 (9)0.0017 (8)0.0014 (7)0.0052 (8)
C100.0745 (15)0.0751 (15)0.0585 (13)0.0034 (13)0.0242 (12)0.0165 (12)
C110.0416 (10)0.0356 (9)0.0409 (10)0.0032 (8)0.0054 (8)0.0024 (8)
C120.0612 (12)0.0375 (9)0.0475 (11)0.0008 (9)0.0051 (9)0.0054 (8)
C130.0448 (10)0.0434 (10)0.0404 (10)0.0018 (8)0.0019 (8)0.0085 (8)
C140.0943 (18)0.0528 (13)0.0664 (14)0.0206 (12)0.0132 (13)0.0048 (11)
C150.0378 (8)0.0311 (8)0.0447 (9)0.0030 (7)0.0022 (8)0.0036 (8)
C160.0441 (10)0.0442 (10)0.0511 (11)0.0013 (9)0.0054 (9)0.0079 (9)
C170.0622 (13)0.0578 (12)0.0456 (11)0.0081 (11)0.0035 (10)0.0086 (10)
C180.0603 (13)0.0543 (12)0.0551 (13)0.0113 (11)0.0128 (10)0.0035 (10)
C190.0465 (11)0.0511 (12)0.0681 (14)0.0030 (9)0.0072 (10)0.0021 (10)
C200.0457 (10)0.0489 (10)0.0518 (11)0.0047 (9)0.0016 (9)0.0105 (10)
N10.0487 (9)0.0488 (9)0.0399 (8)0.0015 (8)0.0035 (7)0.0068 (7)
N20.0428 (8)0.0547 (9)0.0365 (8)0.0070 (7)0.0034 (7)0.0004 (7)
O10.0466 (7)0.0437 (7)0.0435 (7)0.0041 (6)0.0056 (6)0.0017 (6)
O20.0539 (8)0.0677 (9)0.0592 (9)0.0230 (8)0.0151 (7)0.0061 (7)
O30.0579 (8)0.0492 (7)0.0535 (8)0.0079 (7)0.0176 (7)0.0091 (7)
Geometric parameters (Å, º) top
C1—N11.388 (2)C10—H10C0.9600
C1—C21.388 (3)C11—O11.427 (2)
C1—C61.394 (2)C11—C151.504 (2)
C2—C31.369 (3)C11—H110.9800
C2—H20.9300C12—O11.431 (2)
C3—C41.389 (3)C12—C131.491 (3)
C3—H30.9300C12—C141.504 (3)
C4—C51.371 (3)C12—H120.9800
C4—H40.9300C13—N11.313 (2)
C5—C61.379 (3)C13—N21.360 (2)
C5—H50.9300C14—H14A0.9600
C6—N21.381 (2)C14—H14B0.9600
C7—N21.447 (2)C14—H14C0.9600
C7—C81.521 (2)C15—C161.378 (3)
C7—H7A0.9700C15—C201.379 (2)
C7—H7B0.9700C16—C171.380 (3)
C8—C91.508 (2)C16—H160.9300
C8—C111.537 (2)C17—C181.360 (3)
C8—H80.9800C17—H170.9300
C9—O21.196 (2)C18—C191.374 (3)
C9—O31.316 (2)C18—H180.9300
C10—O31.440 (2)C19—C201.373 (3)
C10—H10A0.9600C19—H190.9300
C10—H10B0.9600C20—H200.9300
N1—C1—C2130.01 (17)O1—C11—H11109.0
N1—C1—C6110.46 (15)C15—C11—H11109.0
C2—C1—C6119.49 (17)C8—C11—H11109.0
C3—C2—C1117.90 (18)O1—C12—C13108.86 (14)
C3—C2—H2121.0O1—C12—C14107.67 (17)
C1—C2—H2121.0C13—C12—C14112.14 (17)
C2—C3—C4121.64 (19)O1—C12—H12109.4
C2—C3—H3119.2C13—C12—H12109.4
C4—C3—H3119.2C14—C12—H12109.4
C5—C4—C3121.59 (19)N1—C13—N2113.56 (16)
C5—C4—H4119.2N1—C13—C12126.81 (16)
C3—C4—H4119.2N2—C13—C12119.43 (16)
C4—C5—C6116.54 (18)C12—C14—H14A109.5
C4—C5—H5121.7C12—C14—H14B109.5
C6—C5—H5121.7H14A—C14—H14B109.5
C5—C6—N2132.18 (17)C12—C14—H14C109.5
C5—C6—C1122.82 (17)H14A—C14—H14C109.5
N2—C6—C1104.98 (15)H14B—C14—H14C109.5
N2—C7—C8113.43 (14)C16—C15—C20118.52 (18)
N2—C7—H7A108.9C16—C15—C11121.05 (15)
C8—C7—H7A108.9C20—C15—C11120.42 (17)
N2—C7—H7B108.9C15—C16—C17120.30 (18)
C8—C7—H7B108.9C15—C16—H16119.8
H7A—C7—H7B107.7C17—C16—H16119.8
C9—C8—C7106.26 (13)C18—C17—C16120.76 (19)
C9—C8—C11109.21 (14)C18—C17—H17119.6
C7—C8—C11114.35 (15)C16—C17—H17119.6
C9—C8—H8109.0C17—C18—C19119.40 (19)
C7—C8—H8109.0C17—C18—H18120.3
C11—C8—H8109.0C19—C18—H18120.3
O2—C9—O3124.16 (16)C20—C19—C18120.24 (19)
O2—C9—C8123.49 (16)C20—C19—H19119.9
O3—C9—C8112.31 (14)C18—C19—H19119.9
O3—C10—H10A109.5C19—C20—C15120.77 (19)
O3—C10—H10B109.5C19—C20—H20119.6
H10A—C10—H10B109.5C15—C20—H20119.6
O3—C10—H10C109.5C13—N1—C1104.27 (15)
H10A—C10—H10C109.5C13—N2—C6106.69 (14)
H10B—C10—H10C109.5C13—N2—C7126.10 (15)
O1—C11—C15107.31 (14)C6—N2—C7127.21 (15)
O1—C11—C8112.11 (13)C11—O1—C12116.85 (14)
C15—C11—C8110.49 (14)C9—O3—C10116.93 (15)
N1—C1—C2—C3176.13 (17)C20—C15—C16—C170.4 (3)
C6—C1—C2—C31.1 (3)C11—C15—C16—C17179.17 (17)
C1—C2—C3—C40.3 (3)C15—C16—C17—C180.5 (3)
C2—C3—C4—C50.6 (3)C16—C17—C18—C190.9 (3)
C3—C4—C5—C60.6 (3)C17—C18—C19—C200.4 (3)
C4—C5—C6—N2177.99 (19)C18—C19—C20—C150.5 (3)
C4—C5—C6—C10.2 (3)C16—C15—C20—C190.9 (3)
N1—C1—C6—C5176.63 (16)C11—C15—C20—C19179.70 (17)
C2—C1—C6—C51.1 (3)N2—C13—N1—C10.64 (19)
N1—C1—C6—N21.64 (19)C12—C13—N1—C1174.24 (17)
C2—C1—C6—N2179.41 (16)C2—C1—N1—C13178.12 (19)
N2—C7—C8—C9168.67 (16)C6—C1—N1—C130.66 (19)
N2—C7—C8—C1170.8 (2)N1—C13—N2—C61.7 (2)
C7—C8—C9—O257.1 (2)C12—C13—N2—C6173.61 (16)
C11—C8—C9—O266.7 (2)N1—C13—N2—C7178.08 (16)
C7—C8—C9—O3120.72 (16)C12—C13—N2—C76.6 (3)
C11—C8—C9—O3115.47 (16)C5—C6—N2—C13176.11 (19)
C9—C8—C11—O1178.71 (14)C1—C6—N2—C131.94 (19)
C7—C8—C11—O159.82 (18)C5—C6—N2—C74.1 (3)
C9—C8—C11—C1561.64 (17)C1—C6—N2—C7177.83 (16)
C7—C8—C11—C15179.47 (14)C8—C7—N2—C1364.6 (2)
O1—C12—C13—N1114.80 (19)C8—C7—N2—C6115.64 (19)
C14—C12—C13—N14.2 (3)C15—C11—O1—C12164.34 (14)
O1—C12—C13—N259.8 (2)C8—C11—O1—C1274.17 (18)
C14—C12—C13—N2178.84 (17)C13—C12—O1—C1190.09 (18)
O1—C11—C15—C16139.65 (16)C14—C12—O1—C11148.12 (16)
C8—C11—C15—C1697.85 (19)O2—C9—O3—C100.7 (3)
O1—C11—C15—C2041.6 (2)C8—C9—O3—C10178.51 (17)
C8—C11—C15—C2080.90 (19)
Hydrogen-bond geometry (Å, º) for (I) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O2i0.982.353.225 (2)148
Symmetry code: (i) x1/2, y, z.

Experimental details

(I)(II)
Crystal data
Chemical formulaC19H18N2O3C20H20N2O3
Mr322.35336.38
Crystal system, space groupOrthorhombic, Pca21Orthorhombic, P212121
Temperature (K)293293
a, b, c (Å)9.9238 (13), 7.3322 (10), 23.028 (3)9.1115 (7), 9.6470 (8), 19.4856 (15)
V3)1675.6 (4)1712.8 (2)
Z44
Radiation typeMo KαMo Kα
µ (mm1)0.090.09
Crystal size (mm)0.21 × 0.19 × 0.180.21 × 0.19 × 0.18
Data collection
DiffractometerBruker SMART APEXII CCD
diffractometer
Bruker SMART APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Multi-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.982, 0.9840.981, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
15223, 3639, 2782 30423, 3847, 2958
Rint0.0230.043
(sin θ/λ)max1)0.6370.645
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.089, 1.04 0.037, 0.089, 1.06
No. of reflections35873844
No. of parameters217226
No. of restraints10
H-atom treatmentH-atom parameters constrainedH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.13, 0.130.15, 0.13

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

 

Acknowledgements

The authors thank Dr Babu Varghese, SAIF, IIT, Chennai, India, for the data collection.

References

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