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ISSN: 2056-9890

N,N′-Di-tert-butyl-N′′-(2-chloro­acet­yl)phospho­ric tri­amide

aDepartment of Chemistry, Ferdowsi University of Mashhad, Mashhad 91779, Iran, and bDepartment of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
*Correspondence e-mail: mehrdad_pourayoubi@yahoo.com

(Received 2 September 2011; accepted 26 September 2011; online 5 October 2011)

The P atom in the title mol­ecule, C10H23ClN3O2P, has a distorted tetra­hedral coordination. In the C(O)NHP(O) unit, which has syn-oriented phosphoryl and N—H groups, the P—N bond of 1.703 (2) Å is longer and the O—P—N angle of 103.86 (7)° is contracted compared with the respective values in the two P(O)NHC(CH3)3 units [P—N = 1.632 (2) and 1.624 (2) Å; O—P—N = 116.80 (8) and 115.32 (8)°]. In the crystal, each mol­ecule is hydrogen bonded to two adjacent mol­ecules via N—H⋯O hydrogen bonds, forming a linear sequence of alternating R22(8) and R22(12)/R21(6)-fused rings along [010]. The O atom of the carbonyl group acts as a double H-atom acceptor.

Related literature

For compounds containing a C(O)NHP(O) skeleton and related bond lengths and angles, see: Pourayoubi et al. (2011[Pourayoubi, M., Tarahhomi, A., Saneei, A., Rheingold, A. L. & Golen, J. A. (2011). Acta Cryst. C67, o265-o272.]). For the graph-set description of hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For double hydrogen-bond acceptors, see: Steiner (2002[Steiner, T. (2002). Angew. Chem. Int. Ed. 41, 48-76.]).

[Scheme 1]

Experimental

Crystal data
  • C10H23ClN3O2P

  • Mr = 283.73

  • Monoclinic, C 2/c

  • a = 16.4781 (5) Å

  • b = 9.8872 (2) Å

  • c = 19.6509 (6) Å

  • β = 111.5747 (12)°

  • V = 2977.26 (14) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.36 mm−1

  • T = 173 K

  • 0.16 × 0.14 × 0.12 mm

Data collection
  • Nonius KappaCCD diffractometer with APEXII CCD

  • Absorption correction: multi-scan (SORTAV; Blessing, 1997[Blessing, R. H. (1997). J. Appl. Cryst. 30, 421-426.]) Tmin = 0.945, Tmax = 0.958

  • 6472 measured reflections

  • 3410 independent reflections

  • 2937 reflections with I > 2σ(I)

  • Rint = 0.026

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.103

  • S = 1.10

  • 3410 reflections

  • 169 parameters

  • 3 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.32 e Å−3

  • Δρmin = −0.32 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N⋯O2i 0.87 (1) 1.92 (1) 2.778 (2) 175 (2)
N2—H2N⋯O1ii 0.85 (1) 2.56 (1) 3.337 (2) 153 (2)
N3—H3N⋯O1ii 0.86 (1) 2.12 (1) 2.979 (2) 175 (2)
Symmetry codes: (i) [-x+{\script{3\over 2}}, -y+{\script{1\over 2}}, -z]; (ii) [-x+{\script{3\over 2}}, -y-{\script{1\over 2}}, -z].

Data collection: COLLECT (Hooft, 1998[Hooft, R. (1998). COLLECT. Nonius BV, Delft. The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); program(s) used to solve structure: SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]); program(s) used to refine structure: SHELXL97 (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.]); software used to prepare material for publication: SHELXL97 and enCIFer (Allen et al., 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.]).

Supporting information


Comment top

The structure of the title molecule, P(O)[NHC(O)CH2Cl][NHC(CH3)3]2 (Fig. 1), was determined as a part of the work on the synthesis of new phosphoramidate compounds containing a P(O)NHC(O) moiety (Pourayoubi et al., 2011).

Single crystals were obtained from a solution of CHCl3 after slow evaporation at room temperature. The PO and CO bond lengths and the P—N—C bond angles are within the expected values for this category of molecules (Pourayoubi et al., 2011). The P atom has a distorted tetrahedral configuration, as has been noted for the other phosphoric triamides. As expected, the P—N2 and P—N3 bonds are shorter than the P—N1 bond. In the C(O)NHP(O) moiety, the phosphoryl group has a syn orientation with respect to the N—H unit. The two other N—H units have an anti configuration relative to the PO group.

In the crystal packing, each molecule is H-bonded to two neighbouring molecules through the NC(O)NHP(O)—H···(O)P hydrogen bonds and the [N—H]2···(O)C grouping, forming a sequence of alternated R22(8) and R22(12)R21(6) rings (for graph-set definition in hydrogen bond motifs, see: Bernstein et al., 1995) in a linear arrangement parallel to the y axis, Fig. 2 and Table 1. The carbonyl oxygen atom acts as a double hydrogen bond acceptor (Steiner, 2002).

Related literature top

For compounds containing a C(O)NHP(O) skeleton and related bond lengths and angles, see: Pourayoubi et al. (2011). For the graph-set description of hydrogen-bond motifs, see: Bernstein et al. (1995). For double hydrogen-bond acceptors, see: Steiner (2002).

Experimental top

Synthesis of CH2ClC(O)NHP(O)Cl2: The reaction of phosphorus pentachloride (33.9 mmol) and 2-chloroacetamide (33.9 mmol) in dry benzene (40 ml) at 353 K (3 h) and then the treatment of formic acid (33.9 mmol) at ice-bath temperature (2.5 h), then removing the solvent in vacuum, leads to the formation of CH2ClC(O)NHP(O)Cl2 as solid product.

Synthesis of the title molecule: To a solution of CH2ClC(O)NHP(O)Cl2 (2.42 mmol) in CHCl3 (20 ml), a solution of tert-butylamine (9.68 mmol) in CHCl3 (10 ml) was added dropwise at 273 K. After 4 h of stirring, the solvent was evaporated in vacuum. The obtained solid was washed with distilled water. Single crystals were obtained from a solution of the title molecule in CHCl3 after slow evaporation at room temperature. IR (KBr, cm-1): 3376, 3324, 3104, 2971, 2913, 1692, 1486, 1396, 1186, 1023, 880, 818.

Refinement top

H atoms were positioned geometrically with C—H = 0.99 and 0.98 Å for methylene and methyl H atoms, respectively, and with constrained distances N—H = 0.87 (1) Å in a riding model on their parent atoms with Uiso(H) = 1.2 times Ueq(N/C); the positions of H atoms of the methyl groups were rotationally optimized. Few low angle reflections were omitted as they were located behind the beam stop.

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Figures top
[Figure 1] Fig. 1. An ORTEP drawing of the title molecule with labeling. Displacement ellipsoids are given at 50% probability level.
[Figure 2] Fig. 2. Part of the crystal packing with hydrogen bonds shown as dotted lines. Only H atoms involved in hydrogen bonds are shown.
N,N'-Di-tert-butyl-N''-(2-chloroacetyl)phosphoric triamide top
Crystal data top
C10H23ClN3O2PF(000) = 1216
Mr = 283.73Dx = 1.266 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3520 reflections
a = 16.4781 (5) Åθ = 1.0–27.5°
b = 9.8872 (2) ŵ = 0.36 mm1
c = 19.6509 (6) ÅT = 173 K
β = 111.5747 (12)°Prism, colorless
V = 2977.26 (14) Å30.16 × 0.14 × 0.12 mm
Z = 8
Data collection top
Nonius KappaCCD
diffractometer with APEXII CCD
3410 independent reflections
Radiation source: fine-focus sealed tube2937 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
ω and ϕ scansθmax = 27.5°, θmin = 2.5°
Absorption correction: multi-scan
(SORTAV; Blessing, 1997)
h = 2121
Tmin = 0.945, Tmax = 0.958k = 1112
6472 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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.103H atoms treated by a mixture of independent and constrained refinement
S = 1.10 w = 1/[σ2(Fo2) + (0.0338P)2 + 4.5534P]
where P = (Fo2 + 2Fc2)/3
3410 reflections(Δ/σ)max = 0.001
169 parametersΔρmax = 0.32 e Å3
3 restraintsΔρmin = 0.32 e Å3
Crystal data top
C10H23ClN3O2PV = 2977.26 (14) Å3
Mr = 283.73Z = 8
Monoclinic, C2/cMo Kα radiation
a = 16.4781 (5) ŵ = 0.36 mm1
b = 9.8872 (2) ÅT = 173 K
c = 19.6509 (6) Å0.16 × 0.14 × 0.12 mm
β = 111.5747 (12)°
Data collection top
Nonius KappaCCD
diffractometer with APEXII CCD
3410 independent reflections
Absorption correction: multi-scan
(SORTAV; Blessing, 1997)
2937 reflections with I > 2σ(I)
Tmin = 0.945, Tmax = 0.958Rint = 0.026
6472 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0433 restraints
wR(F2) = 0.103H atoms treated by a mixture of independent and constrained refinement
S = 1.10Δρmax = 0.32 e Å3
3410 reflectionsΔρmin = 0.32 e Å3
169 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
Cl10.94023 (4)0.09873 (6)0.09379 (3)0.04413 (16)
P10.70496 (3)0.03761 (4)0.02879 (3)0.02208 (13)
O10.81276 (10)0.15073 (13)0.02559 (9)0.0381 (4)
O20.67546 (9)0.17456 (12)0.03962 (7)0.0287 (3)
N10.77781 (10)0.06685 (14)0.01251 (8)0.0233 (3)
H1N0.7907 (13)0.1494 (12)0.0191 (11)0.028*
N20.75351 (11)0.04883 (15)0.10356 (8)0.0284 (4)
H2N0.7503 (14)0.1342 (10)0.0981 (12)0.034*
N30.63044 (10)0.06675 (15)0.02058 (9)0.0248 (3)
H3N0.6432 (13)0.1496 (11)0.0079 (11)0.030*
C10.81982 (11)0.03053 (17)0.03486 (10)0.0235 (4)
C20.87490 (13)0.02675 (19)0.07542 (11)0.0311 (4)
H2A0.91290.09930.04560.037*
H2B0.83610.06720.12210.037*
C30.80542 (12)0.0073 (2)0.17664 (10)0.0280 (4)
C40.86795 (17)0.1160 (3)0.17114 (14)0.0516 (6)
H4A0.90150.15110.22010.062*
H4B0.83470.18990.14000.062*
H4C0.90790.07720.14980.062*
C50.85793 (16)0.1082 (2)0.22316 (12)0.0427 (5)
H5A0.89140.07510.27260.051*
H5B0.89810.14400.20110.051*
H5C0.81820.18010.22580.051*
C60.74387 (16)0.0653 (3)0.21120 (13)0.0521 (7)
H6A0.77800.10170.25970.063*
H6B0.70520.00640.21600.063*
H6C0.70880.13770.18010.063*
C70.56724 (12)0.04828 (19)0.09668 (10)0.0270 (4)
C80.50741 (14)0.1718 (2)0.11260 (13)0.0392 (5)
H8A0.46490.16670.16290.047*
H8B0.47650.17370.07850.047*
H8C0.54240.25420.10670.047*
C90.51410 (14)0.0797 (2)0.10192 (12)0.0381 (5)
H9A0.47050.08840.15160.046*
H9B0.55300.15840.09070.046*
H9C0.48460.07470.06690.046*
C100.61356 (14)0.0416 (2)0.15144 (11)0.0380 (5)
H10A0.57010.04390.20140.046*
H10B0.65300.11910.14390.046*
H10C0.64720.04250.14400.046*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0473 (3)0.0452 (3)0.0496 (3)0.0194 (3)0.0291 (3)0.0033 (2)
P10.0271 (2)0.0159 (2)0.0265 (2)0.00014 (17)0.01385 (19)0.00075 (17)
O10.0427 (8)0.0170 (7)0.0628 (10)0.0058 (6)0.0291 (8)0.0069 (6)
O20.0354 (7)0.0170 (6)0.0402 (8)0.0001 (5)0.0216 (6)0.0002 (5)
N10.0280 (8)0.0140 (7)0.0319 (8)0.0010 (6)0.0157 (6)0.0008 (6)
N20.0405 (9)0.0180 (7)0.0265 (8)0.0030 (7)0.0122 (7)0.0004 (6)
N30.0278 (8)0.0151 (7)0.0313 (8)0.0003 (6)0.0107 (7)0.0012 (6)
C10.0246 (8)0.0190 (9)0.0266 (9)0.0035 (7)0.0090 (7)0.0023 (7)
C20.0355 (10)0.0263 (10)0.0390 (11)0.0072 (8)0.0224 (9)0.0028 (8)
C30.0292 (9)0.0277 (10)0.0274 (9)0.0009 (8)0.0106 (8)0.0018 (8)
C40.0477 (14)0.0489 (14)0.0491 (14)0.0168 (12)0.0070 (11)0.0031 (11)
C50.0546 (14)0.0398 (12)0.0302 (10)0.0109 (11)0.0115 (10)0.0018 (9)
C60.0453 (13)0.0766 (18)0.0349 (12)0.0185 (13)0.0153 (10)0.0099 (12)
C70.0263 (9)0.0257 (9)0.0286 (9)0.0006 (7)0.0096 (7)0.0014 (7)
C80.0342 (11)0.0327 (11)0.0460 (12)0.0070 (9)0.0092 (9)0.0028 (9)
C90.0351 (11)0.0327 (11)0.0420 (12)0.0090 (9)0.0086 (9)0.0019 (9)
C100.0357 (11)0.0500 (13)0.0278 (10)0.0014 (10)0.0110 (9)0.0052 (9)
Geometric parameters (Å, º) top
Cl1—C21.7647 (19)C4—H4C0.9800
P1—O21.4803 (13)C5—H5A0.9800
P1—N31.6241 (16)C5—H5B0.9800
P1—N21.6324 (16)C5—H5C0.9800
P1—N11.7030 (15)C6—H6A0.9800
O1—C11.214 (2)C6—H6B0.9800
N1—C11.350 (2)C6—H6C0.9800
N1—H1N0.866 (9)C7—C91.520 (3)
N2—C31.483 (2)C7—C81.528 (3)
N2—H2N0.850 (9)C7—C101.533 (3)
N3—C71.486 (2)C8—H8A0.9800
N3—H3N0.859 (9)C8—H8B0.9800
C1—C21.520 (2)C8—H8C0.9800
C2—H2A0.9900C9—H9A0.9800
C2—H2B0.9900C9—H9B0.9800
C3—C51.519 (3)C9—H9C0.9800
C3—C41.520 (3)C10—H10A0.9800
C3—C61.525 (3)C10—H10B0.9800
C4—H4A0.9800C10—H10C0.9800
C4—H4B0.9800
O2—P1—N3116.80 (8)C3—C5—H5A109.5
O2—P1—N2115.32 (8)C3—C5—H5B109.5
N3—P1—N2102.57 (8)H5A—C5—H5B109.5
O2—P1—N1103.86 (7)C3—C5—H5C109.5
N3—P1—N1109.50 (8)H5A—C5—H5C109.5
N2—P1—N1108.65 (8)H5B—C5—H5C109.5
C1—N1—P1124.72 (12)C3—C6—H6A109.5
C1—N1—H1N116.1 (14)C3—C6—H6B109.5
P1—N1—H1N119.1 (14)H6A—C6—H6B109.5
C3—N2—P1126.36 (13)C3—C6—H6C109.5
C3—N2—H2N118.8 (15)H6A—C6—H6C109.5
P1—N2—H2N114.8 (15)H6B—C6—H6C109.5
C7—N3—P1128.25 (12)N3—C7—C9110.09 (15)
C7—N3—H3N114.5 (14)N3—C7—C8105.57 (15)
P1—N3—H3N112.5 (14)C9—C7—C8109.82 (17)
O1—C1—N1124.08 (17)N3—C7—C10111.48 (15)
O1—C1—C2123.48 (16)C9—C7—C10109.86 (17)
N1—C1—C2112.41 (15)C8—C7—C10109.94 (17)
C1—C2—Cl1111.84 (13)C7—C8—H8A109.5
C1—C2—H2A109.2C7—C8—H8B109.5
Cl1—C2—H2A109.2H8A—C8—H8B109.5
C1—C2—H2B109.2C7—C8—H8C109.5
Cl1—C2—H2B109.2H8A—C8—H8C109.5
H2A—C2—H2B107.9H8B—C8—H8C109.5
N2—C3—C5107.42 (16)C7—C9—H9A109.5
N2—C3—C4111.14 (17)C7—C9—H9B109.5
C5—C3—C4108.87 (18)H9A—C9—H9B109.5
N2—C3—C6109.32 (16)C7—C9—H9C109.5
C5—C3—C6109.85 (18)H9A—C9—H9C109.5
C4—C3—C6110.2 (2)H9B—C9—H9C109.5
C3—C4—H4A109.5C7—C10—H10A109.5
C3—C4—H4B109.5C7—C10—H10B109.5
H4A—C4—H4B109.5H10A—C10—H10B109.5
C3—C4—H4C109.5C7—C10—H10C109.5
H4A—C4—H4C109.5H10A—C10—H10C109.5
H4B—C4—H4C109.5H10B—C10—H10C109.5
O2—P1—N1—C1177.92 (15)P1—N1—C1—C2175.25 (13)
N3—P1—N1—C152.46 (17)O1—C1—C2—Cl19.6 (3)
N2—P1—N1—C158.83 (17)N1—C1—C2—Cl1172.32 (13)
O2—P1—N2—C329.69 (19)P1—N2—C3—C5164.41 (15)
N3—P1—N2—C3157.76 (15)P1—N2—C3—C445.4 (2)
N1—P1—N2—C386.38 (16)P1—N2—C3—C676.4 (2)
O2—P1—N3—C755.94 (17)P1—N3—C7—C956.2 (2)
N2—P1—N3—C7176.93 (15)P1—N3—C7—C8174.63 (14)
N1—P1—N3—C761.68 (16)P1—N3—C7—C1066.0 (2)
P1—N1—C1—O12.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O2i0.87 (1)1.92 (1)2.778 (2)175 (2)
N2—H2N···O1ii0.85 (1)2.56 (1)3.337 (2)153 (2)
N3—H3N···O1ii0.86 (1)2.12 (1)2.979 (2)175 (2)
Symmetry codes: (i) x+3/2, y+1/2, z; (ii) x+3/2, y1/2, z.

Experimental details

Crystal data
Chemical formulaC10H23ClN3O2P
Mr283.73
Crystal system, space groupMonoclinic, C2/c
Temperature (K)173
a, b, c (Å)16.4781 (5), 9.8872 (2), 19.6509 (6)
β (°) 111.5747 (12)
V3)2977.26 (14)
Z8
Radiation typeMo Kα
µ (mm1)0.36
Crystal size (mm)0.16 × 0.14 × 0.12
Data collection
DiffractometerNonius KappaCCD
diffractometer with APEXII CCD
Absorption correctionMulti-scan
(SORTAV; Blessing, 1997)
Tmin, Tmax0.945, 0.958
No. of measured, independent and
observed [I > 2σ(I)] reflections
6472, 3410, 2937
Rint0.026
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.103, 1.10
No. of reflections3410
No. of parameters169
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.32, 0.32

Computer programs: COLLECT (Hooft, 1998), DENZO (Otwinowski & Minor, 1997), SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1993), Mercury (Macrae et al., 2008), SHELXL97 (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O2i0.866 (9)1.915 (10)2.778 (2)175 (2)
N2—H2N···O1ii0.850 (9)2.558 (13)3.337 (2)152.8 (19)
N3—H3N···O1ii0.859 (9)2.123 (10)2.979 (2)175 (2)
Symmetry codes: (i) x+3/2, y+1/2, z; (ii) x+3/2, y1/2, z.
 

Acknowledgements

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

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