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ISSN: 2056-9890

N-(2-Chloro-2,2-di­fluoro­acet­yl)-N′,N′′-diiso­propyl­phospho­ric tri­amide

aDepartment of Chemistry, Ferdowsi University of Mashhad, Mashhad 91779, Iran
*Correspondence e-mail: mehrdad_pourayoubi@yahoo.com

(Received 6 February 2011; accepted 14 February 2011; online 19 February 2011)

In the title compound, C8H17ClF2N3O2P, the phosphoryl group and the NH unit of the C(O)NHP(O) moiety adopt a syn conformation with respect to each other. The P atom is in a tetra­hedral coordination environment and the environment of the N atom of the C(O)NHP(O) moiety is essentially planar. In the crystal, adjacent mol­ecules are linked via N—H⋯O =P and N—H⋯O =C hydrogen bonds, building R22(8) and R22(12) rings in a linear arrangement parallel to [110].

Related literature

For metal complexes of phosphoryl donor ligands, see: Gholivand et al. (2010[Gholivand, K., Mahzouni, H. R., Pourayoubi, M. & Amiri, S. (2010). Inorg. Chim. Acta, 363, 2318-2324.]). For a phospho­ric triamide compound having a C(=O)NHP(=O) skeleton, see: Pourayoubi et al. (2010[Pourayoubi, M., Tarahhomi, A., Rheingold, A. L. & Golen, J. A. (2010). Acta Cryst. E66, o3159.]). For hydrogen-bond motifs, see: Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]); Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For the synthesis of the starting material, CClF2C(O)NHP(O)Cl2, see: Iriarte et al. (2008[Iriarte, A. G., Erben, M. F., Gholivand, K., Jios, J. L., Ulic, S. E. & Védova, C. O. D. (2008). J. Mol. Struct. 886, 66-71.]).

[Scheme 1]

Experimental

Crystal data
  • C8H17ClF2N3O2P

  • Mr = 291.67

  • Triclinic, [P \overline 1]

  • a = 8.1993 (7) Å

  • b = 9.6735 (9) Å

  • c = 9.8331 (9) Å

  • α = 99.784 (2)°

  • β = 105.999 (2)°

  • γ = 110.770 (2)°

  • V = 669.18 (10) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.42 mm−1

  • T = 100 K

  • 0.26 × 0.19 × 0.16 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.602, Tmax = 0.750

  • 9089 measured reflections

  • 4218 independent reflections

  • 3337 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.095

  • S = 1.04

  • 4218 reflections

  • 158 parameters

  • H-atom parameters constrained

  • Δρmax = 0.56 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2i 0.88 1.87 2.7295 (13) 164
N3—H3⋯O1ii 0.85 2.14 2.9645 (14) 163
Symmetry codes: (i) -x+1, -y+2, -z; (ii) -x, -y+1, -z.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Carbacylamidophosphates with a –C(O)NHP(O)- skeleton have attracted attention because of their roles as the O,O'-donor ligands for metal complexation (Gholivand et al., 2010). Following our previous works about phosphorus compounds containing C(O)NHP(O) moiety such as P(O)[NHC(O)C6H3(2,6-F2)][NHC(CH3)3]2 (Pourayoubi et al., 2010), we report here on the synthesis and crystal structure of P(O)[NHC(O)CClF2][NH(C3H7)]2. Single crystals of title compound were obtained from a solution of CH3OH and CH3CN after a slow evaporation at room temperature.

The phosphoryl group and NH unit are syn to each other and the phosphorus atom has a slightly distorted tetrahedral configuration (Fig. 1). The bond angles around the P atom are in the range of 103.30 (6)° to 119.69 (6)°. The P—N2 and P—N3 bonds (with bond lengths of 1.6262 (12) Å and 1.6190 (11) Å) are shorter than the P—N1 bond (1.7039 (11) Å). The environment of nitrogen N1 atom is essentially planar. The PO bond length of 1.4768 (9) Å is standard for phosphoramidate compounds.

In the crystal structure, adjacent molecules are linked via N—H···O P and N—H···O C hydrogen bonds, building R22(8) and R22(12) rings (Etter et al., 1990; Bernstein et al., 1995) in a linear arrangement parallel to the ab plane in the direction of [110] axis (Table 1, Fig. 2).

Related literature top

For metal complexes of phosphoryl donor ligands, see: Gholivand et al. (2010). For a phosphoric triamide compound having a C(O)NHP( O) skeleton, see: Pourayoubi et al. (2010). For hydrogen-bond motifs, see: Etter et al. (1990); Bernstein et al. (1995). For the synthesis of the starting material, CClF2C(O)NHP(O)Cl2, see: Iriarte et al. (2008).

Experimental top

Synthesis of CClF2C(O)NHP(O)Cl2 CClF2C(O)NHP(O)Cl2 was prepared according to procedure reported by Iriarte et al. (2008) from a reaction between phosphorus pentachloride (16.91 mmol) and CClF2C(O)NH2 (16.91 mmol) in dry CCl4 at 358 K (3 h) and then the treatment of formic acid (16.91 mmol) at ice bath temperature; then removing of solvent in vacuum to yield CClF2C(O)NHP(O)Cl2.

Synthesis of title compound To a solution of CClF2C(O)NHP(O)Cl2 (2.09 mmol) in dry CHCl3, a solution of N-iso-propylamine (8.36 mmol) in dry CHCl3 was added dropwise and stirred at 273 K. After 4 h, the solvent was evaporated at room temperature. The solid was washed with H2O. The product was obtained after recrystallization from a methanol/acetonitrile mixture (4:1) after a slow evaporation at room temperature. IR (KBr, cm-1): 3400, 3057, 2910, 2890, 2730, 1740 (CO), 1500, 1260, 1218, 1165, 1118, 1095, 978, 920, 840, 738, 720.

Refinement top

All H atoms attached to C atoms and the planar N1 atom were fixed geometrically and treated as riding with C—H = 0.98 Å (methyl) or 1.0 Å (methine) and N—H = 0.86 Å with Uiso(H) = 1.2Ueq(Cmethine or N) or Uiso(H) = 1.5Ueq(CH3). H atoms for N2 and N3 were located in difference Fourier maps and included in the subsequent refinement using restraints (N-H= 0.86 (1)Å with Uiso(H) = 1.5Ueq(N). In the last cycles of refinement they were treated as riding on their parent N atoms.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXL97 (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. An ORTEP-style plot of title compound with the atom labeling scheme. Ellipsoids are shown at the 50% probability level. H atoms are represented as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Partial packing view showing the formation of the chain through N-H···O hydrogen bonds which are shown as dashed lines. H atoms not involved in hydrogen bondings have been omitted for the sake of clarity. [Symmetry codes: (i) -x+1, -y+2, -z; (ii) -x, -y+1, -z]
N-(2-Chloro-2,2-difluoroacetyl)-N',N''- diisopropylphosphoric triamide top
Crystal data top
C8H17ClF2N3O2PZ = 2
Mr = 291.67F(000) = 304
Triclinic, P1Dx = 1.448 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.1993 (7) ÅCell parameters from 2867 reflections
b = 9.6735 (9) Åθ = 2.3–30.9°
c = 9.8331 (9) ŵ = 0.42 mm1
α = 99.784 (2)°T = 100 K
β = 105.999 (2)°Prizm, colorless
γ = 110.770 (2)°0.26 × 0.19 × 0.16 mm
V = 669.18 (10) Å3
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
4218 independent reflections
Radiation source: fine-focus sealed tube3337 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
ϕ and ω scansθmax = 31.0°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1111
Tmin = 0.602, Tmax = 0.750k = 1414
9089 measured reflectionsl = 1414
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) = 0.095H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0527P)2 + 0.0127P]
where P = (Fo2 + 2Fc2)/3
4218 reflections(Δ/σ)max < 0.001
158 parametersΔρmax = 0.56 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
C8H17ClF2N3O2Pγ = 110.770 (2)°
Mr = 291.67V = 669.18 (10) Å3
Triclinic, P1Z = 2
a = 8.1993 (7) ÅMo Kα radiation
b = 9.6735 (9) ŵ = 0.42 mm1
c = 9.8331 (9) ÅT = 100 K
α = 99.784 (2)°0.26 × 0.19 × 0.16 mm
β = 105.999 (2)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
4218 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
3337 reflections with I > 2σ(I)
Tmin = 0.602, Tmax = 0.750Rint = 0.024
9089 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0360 restraints
wR(F2) = 0.095H-atom parameters constrained
S = 1.04Δρmax = 0.56 e Å3
4218 reflectionsΔρmin = 0.30 e Å3
158 parameters
Special details top

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 > 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
P10.23257 (4)0.86972 (4)0.03714 (4)0.01390 (8)
Cl10.30477 (6)0.56630 (4)0.36890 (4)0.03081 (10)
F10.54717 (11)0.63181 (10)0.11562 (10)0.0284 (2)
F20.31465 (14)0.40675 (9)0.19141 (11)0.0322 (2)
O10.10801 (14)0.52987 (10)0.10574 (11)0.0238 (2)
O20.37834 (13)1.03015 (10)0.10823 (10)0.0196 (2)
N10.33089 (14)0.77459 (12)0.05183 (12)0.0146 (2)
H10.43680.82920.06090.018*
N20.03816 (15)0.83557 (13)0.09290 (12)0.0182 (2)
H20.04830.84200.06610.022*
N30.16459 (15)0.79008 (12)0.15566 (12)0.0155 (2)
H30.07530.69930.12250.019*
C10.25344 (17)0.61960 (14)0.10878 (14)0.0153 (2)
C20.36184 (19)0.55503 (15)0.18656 (15)0.0192 (3)
C30.02381 (19)0.84469 (16)0.24394 (15)0.0201 (3)
H3A0.07040.77210.28740.024*
C40.1816 (2)0.78961 (18)0.33779 (16)0.0259 (3)
H4A0.25250.68370.33860.039*
H4B0.19390.79160.43940.039*
H4C0.23090.85810.29590.039*
C50.1427 (2)1.00657 (18)0.24315 (16)0.0262 (3)
H5A0.27501.03410.18890.039*
H5B0.10511.08090.19470.039*
H5C0.12461.00900.34530.039*
C60.29579 (18)0.82087 (16)0.30596 (15)0.0208 (3)
H6A0.39760.92770.33610.025*
C70.1941 (2)0.81568 (18)0.41385 (16)0.0268 (3)
H7A0.13660.88880.40810.040*
H7B0.28340.84420.51480.040*
H7C0.09650.71080.38840.040*
C80.3848 (3)0.7080 (2)0.3090 (2)0.0390 (4)
H8A0.45680.71950.24370.058*
H8B0.28670.60200.27490.058*
H8C0.46850.72940.41050.058*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.01625 (15)0.00992 (14)0.01683 (16)0.00349 (11)0.01039 (12)0.00433 (11)
Cl10.0425 (2)0.0345 (2)0.02119 (18)0.01780 (18)0.01803 (16)0.00824 (15)
F10.0208 (4)0.0305 (5)0.0358 (5)0.0133 (4)0.0117 (4)0.0065 (4)
F20.0469 (6)0.0162 (4)0.0489 (6)0.0186 (4)0.0300 (5)0.0147 (4)
O10.0247 (5)0.0128 (4)0.0318 (5)0.0005 (4)0.0187 (4)0.0040 (4)
O20.0237 (5)0.0115 (4)0.0233 (5)0.0026 (4)0.0158 (4)0.0030 (4)
N10.0148 (5)0.0108 (5)0.0195 (5)0.0034 (4)0.0109 (4)0.0043 (4)
N20.0203 (5)0.0223 (5)0.0191 (5)0.0112 (5)0.0126 (4)0.0091 (4)
N30.0153 (5)0.0125 (5)0.0161 (5)0.0012 (4)0.0081 (4)0.0042 (4)
C10.0178 (6)0.0119 (5)0.0171 (6)0.0054 (5)0.0089 (5)0.0047 (4)
C20.0243 (7)0.0134 (6)0.0246 (7)0.0089 (5)0.0131 (5)0.0076 (5)
C30.0255 (7)0.0244 (7)0.0177 (6)0.0151 (6)0.0118 (5)0.0076 (5)
C40.0262 (7)0.0281 (7)0.0222 (7)0.0131 (6)0.0066 (6)0.0045 (6)
C50.0276 (7)0.0329 (8)0.0226 (7)0.0121 (6)0.0129 (6)0.0148 (6)
C60.0176 (6)0.0220 (6)0.0180 (6)0.0032 (5)0.0057 (5)0.0069 (5)
C70.0352 (8)0.0334 (8)0.0180 (6)0.0181 (7)0.0124 (6)0.0099 (6)
C80.0395 (9)0.0669 (12)0.0355 (9)0.0384 (9)0.0212 (8)0.0278 (9)
Geometric parameters (Å, º) top
P1—O21.4768 (9)C3—H3A1.0000
P1—N31.6190 (11)C4—H4A0.9800
P1—N21.6262 (12)C4—H4B0.9800
P1—N11.7039 (11)C4—H4C0.9800
Cl1—C21.7566 (14)C5—H5A0.9800
F1—C21.3366 (16)C5—H5B0.9800
F2—C21.3351 (15)C5—H5C0.9800
O1—C11.2127 (15)C6—C81.513 (2)
N1—C11.3447 (15)C6—C71.5164 (19)
N1—H10.8800C6—H6A1.0000
N2—C31.4775 (17)C7—H7A0.9800
N2—H20.8390C7—H7B0.9800
N3—C61.4754 (17)C7—H7C0.9800
N3—H30.8536C8—H8A0.9800
C1—C21.5399 (17)C8—H8B0.9800
C3—C51.520 (2)C8—H8C0.9800
C3—C41.5207 (19)
O2—P1—N3112.27 (5)C3—C4—H4A109.5
O2—P1—N2119.69 (6)C3—C4—H4B109.5
N3—P1—N2103.94 (6)H4A—C4—H4B109.5
O2—P1—N1105.13 (5)C3—C4—H4C109.5
N3—P1—N1112.31 (5)H4A—C4—H4C109.5
N2—P1—N1103.30 (6)H4B—C4—H4C109.5
C1—N1—P1122.76 (9)C3—C5—H5A109.5
C1—N1—H1118.6C3—C5—H5B109.5
P1—N1—H1118.6H5A—C5—H5B109.5
C3—N2—P1123.77 (9)C3—C5—H5C109.5
C3—N2—H2116.2H5A—C5—H5C109.5
P1—N2—H2117.0H5B—C5—H5C109.5
C6—N3—P1121.89 (8)N3—C6—C8111.29 (12)
C6—N3—H3112.7N3—C6—C7109.51 (11)
P1—N3—H3117.9C8—C6—C7111.49 (12)
O1—C1—N1126.01 (12)N3—C6—H6A108.1
O1—C1—C2118.79 (11)C8—C6—H6A108.1
N1—C1—C2115.19 (10)C7—C6—H6A108.1
F2—C2—F1107.66 (11)C6—C7—H7A109.5
F2—C2—C1109.72 (10)C6—C7—H7B109.5
F1—C2—C1112.14 (11)H7A—C7—H7B109.5
F2—C2—Cl1108.56 (10)C6—C7—H7C109.5
F1—C2—Cl1108.94 (9)H7A—C7—H7C109.5
C1—C2—Cl1109.74 (9)H7B—C7—H7C109.5
N2—C3—C5111.99 (11)C6—C8—H8A109.5
N2—C3—C4108.48 (11)C6—C8—H8B109.5
C5—C3—C4112.00 (12)H8A—C8—H8B109.5
N2—C3—H3A108.1C6—C8—H8C109.5
C5—C3—H3A108.1H8A—C8—H8C109.5
C4—C3—H3A108.1H8B—C8—H8C109.5
O2—P1—N1—C1168.43 (10)O1—C1—C2—F222.92 (17)
N3—P1—N1—C146.05 (12)N1—C1—C2—F2158.19 (11)
N2—P1—N1—C165.33 (11)O1—C1—C2—F1142.50 (13)
O2—P1—N2—C372.29 (12)N1—C1—C2—F138.60 (15)
N3—P1—N2—C3161.47 (10)O1—C1—C2—Cl196.28 (13)
N1—P1—N2—C344.04 (11)N1—C1—C2—Cl182.62 (12)
O2—P1—N3—C636.29 (12)P1—N2—C3—C561.53 (14)
N2—P1—N3—C6167.07 (10)P1—N2—C3—C4174.35 (9)
N1—P1—N3—C681.94 (11)P1—N3—C6—C889.23 (13)
P1—N1—C1—O10.56 (19)P1—N3—C6—C7147.05 (10)
P1—N1—C1—C2179.37 (9)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.881.872.7295 (13)164
N3—H3···O1ii0.852.142.9645 (14)163
Symmetry codes: (i) x+1, y+2, z; (ii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC8H17ClF2N3O2P
Mr291.67
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)8.1993 (7), 9.6735 (9), 9.8331 (9)
α, β, γ (°)99.784 (2), 105.999 (2), 110.770 (2)
V3)669.18 (10)
Z2
Radiation typeMo Kα
µ (mm1)0.42
Crystal size (mm)0.26 × 0.19 × 0.16
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.602, 0.750
No. of measured, independent and
observed [I > 2σ(I)] reflections
9089, 4218, 3337
Rint0.024
(sin θ/λ)max1)0.725
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.095, 1.04
No. of reflections4218
No. of parameters158
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.56, 0.30

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.881.872.7295 (13)164
N3—H3···O1ii0.852.142.9645 (14)163
Symmetry codes: (i) x+1, y+2, z; (ii) x, y+1, z.
 

Acknowledgements

Support of this investigation by Ferdowsi University of Mashhad is gratefully acknowledged.

References

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