tert-Butyl 2-(4-chloro­benzo­yl)-2-methyl­propanoate

Crosse, C.M.; Kelly, E.C.; Logue, M.W.; Luck, R.L.; Maass, J.S.; Mehne, K.C.; Pignotti, L.R.

doi:10.1107/S1600536810003156

organic compounds

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ISSN: 2056-9890

Volume 66| Part 2| February 2010| Pages o493-o494

https://doi.org/10.1107/S1600536810003156

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tert-Butyl 2-(4-chlorobenzoyl)-2-methylpropanoate

Chelsey M. Crosse,^a Emily C. Kelly,^a Marshall W. Logue,^a Rudy L. Luck,^a ^* John S. Maass,^a Katlyn C. Mehne ^a and Louis R. Pignotti ^a

^aDepartment of Chemistry, 1400 Townsend Drive, Michigan Technological University, Houghton, MI 49931, USA
^*Correspondence e-mail: rluck@mtu.edu

(Received 11 January 2010; accepted 25 January 2010; online 30 January 2010)

The title compound, C₁₅H₁₉ClO₃, is bent with a dihedral angle of 72.02 (9)° between the mean planes of the benzene ring and a group encompassing the ester functionality (O=C—O—C). In the crystal, molecules related by inversion symmetry are connected by weak C—H⋯O interactions into infinite chains. These interactions involve H atoms from a methyl group of the dimethyl residue and the O atoms of the ketone on one side of a molecule; on the other side there are interactions between H atoms of the benzene ring and the carbonyl O atoms of the ester functionality. There are no directional interactions between the chains.

Related literature

For the synthesis, spectroscopic characterization and reactivity of the title compound, see: Logue (1974 ); Logue et al. (1975 ). For related structures, see: Crosse et al. (2010 ); Gould et al. (2010 ); Logue et al. (2010 ). For the syntheses and characterization of structurally similar indanone-derived β-keto ester derivatives, see: Mouri et al. (2009 ); Noritake et al. (2008 ); Rigby & Dixon (2008 ). For weak hydrogen-bonded interactions, see: Karle et al. (2009 ).

Experimental

Crystal data

C₁₅H₁₉ClO₃
M_r = 282.75
Triclinic, $[P \overline 1]$
a = 8.601 (3) Å
b = 9.214 (2) Å
c = 11.033 (2) Å
α = 72.67 (2)°
β = 74.62 (2)°
γ = 74.02 (3)°
V = 786.3 (4) Å³
Z = 2
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 291 K
0.30 × 0.30 × 0.30 mm

Data collection

Enraf–Nonius TurboCAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.905, T_max = 0.929
2961 measured reflections
2759 independent reflections
1589 reflections with I > 2σ(I)
R_int = 0.020
3 standard reflections every 166 min intensity decay: 9%

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.125
S = 1.01
2759 reflections
177 parameters
H-atom parameters constrained
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C10—H10A⋯O1ⁱ	0.96	2.58	3.476 (4)	155
C5—H5⋯O2ⁱⁱ	0.93	2.7	3.316 (3)	125
Symmetry codes: (i) -x-1, -y+1, -z; (ii) -x-1, -y+1, -z+1.

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 ); program(s) used to solve structure: SIR2004 (Burla et al., 2005 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ) and Mercury (Macrae et al., 2008 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ) and publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810003156/zl2267sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810003156/zl2267Isup2.hkl

checkCIF report

Comment top

Treatment of 2,2-disubstituted t-butyl β-keto esters with trifluoroacetic acid at room temperature quantitatively generates the corresponding 2,2-disubstituted β-keto acids, which were used to probe the nature of the transition state for the thermal decarboxylation of β-keto acids (Logue et al., 1975). Structurally similar indanone-derived β-keto ester derivatives have been prepared recently (Mouri et al., 2009; Noritake et al., 2008; Rigby & Dixon, 2008). The directing nature of weak C—H···O H-bonds has been noted to be of importance to afford the three dimensional structure observed in these kinds of molecules (Karle et al., 2009).

In this contribution we present the solid state structure of one such 2,2-disubstituted β-keto acid, i.e. the title compound being the para-chlorobenzene derivative. This is the third paper in a series of four dealing with substituted derivatives (H–, CH₃–, Cl- (this paper) and NO₂– on the para-position of the phenyl ring) of the title compound. A more detailed comparison of all four substitution compounds will be given in the fourth paper of this series (Crosse et al., 2010).

The molecule, Fig. 1, displays a bent geometry with a dihedral angle between the mean planes of the phenyl ring and a plane composed of the ester functionality of 72.02 (9)°. Molecules are linked by C—H···O weak hydrogen bonds generating infinite chains as shown in Fig. 2. The phenyl rings are not involved in intercalation or stacking interactions either within or between the chains. Instead, neighbouring t-butyl groups on adjacent chains exhibit hydrophobic stacking.

Related literature top

For the synthesis, spectroscopic characterization and reactivity of the title compound, see: Logue (1974); Logue et al. (1975). For related structures, see: Crosse et al. (2010; Gould et al. (2010); Logue et al. (2010). For the syntheses and characterization of structurally similar indanone-derived β-keto ester derivatives, see: Mouri et al. (2009); Noritake et al. (2008); Rigby & Dixon (2008). For weak hydrogen-bonded interactions, see: Karle et al. (2009). Paper is 3rd in series (ZL2265, ZL2266, ZL2267, ZL2264)

Experimental top

Crystals of the material were synthesized as reported earlier and were grown by evaporation of a solution in hexane (Logue, 1974). M.p. 600–606 K. IR (neat, cm^-1) 2982 (m, ring), 1726 (s, C=O), 1682 (s, O—C=O), 1588 (s), 1488 (m), 1388 (m), 1368 (w), 1273 (m), 1133 (m), 1091.6 (m), 987 (w), 920 (w), 842 (m), 739 (m). ¹H NMR (CDCl₃) δ: 1.27 (s, 9H), 1.47 (s, 6H), 7.36 (d, 2H, J=8.8 Hz), 7.80 (d, 2H, J=9.2 Hz). ¹³C NMR (CDCl₃) δ: 23.8, 27.6, 54.0, 81.9, 130.2, 133.6, 139.0, 173.8, 196.8.

Structure description top

For the synthesis, spectroscopic characterization and reactivity of the title compound, see: Logue (1974); Logue et al. (1975). For related structures, see: Crosse et al. (2010; Gould et al. (2010); Logue et al. (2010). For the syntheses and characterization of structurally similar indanone-derived β-keto ester derivatives, see: Mouri et al. (2009); Noritake et al. (2008); Rigby & Dixon (2008). For weak hydrogen-bonded interactions, see: Karle et al. (2009). Paper is 3rd in series (ZL2265, ZL2266, ZL2267, ZL2264)

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 1999) and publCIF (Westrip, 2010).

Figures top

	Fig. 1. ORTEP-3 (Farrugia, 1997) drawing of the title compound with displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. A Mercury (Macrae et al., 2008) illustration of the packing in the title compound depicting the H-bonded linkages using dashed lines which result in infinite chains.

tert-Butyl 2-(4-chlorobenzoyl)-2-methylpropanoate top

Crystal data top

C₁₅H₁₉ClO₃	Z = 2
M_r = 282.75	F(000) = 300
Triclinic, P1	D_x = 1.194 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.601 (3) Å	Cell parameters from 25 reflections
b = 9.214 (2) Å	θ = 10–15°
c = 11.033 (2) Å	µ = 0.24 mm⁻¹
α = 72.67 (2)°	T = 291 K
β = 74.62 (2)°	Prism, colourless
γ = 74.02 (3)°	0.30 × 0.30 × 0.30 mm
V = 786.3 (4) Å³

Data collection top

Enraf–Nonius TurboCAD-4 diffractometer	1589 reflections with I > 2σ(I)
Radiation source: Enraf Nonius FR590	R_int = 0.020
Graphite monochromator	θ_max = 25.0°, θ_min = 2.0°
non–profiled ω/2τ scans	h = 0→10
Absorption correction: ψ scan (North et al., 1968)	k = −10→10
T_min = 0.905, T_max = 0.929	l = −12→13
2961 measured reflections	3 standard reflections every 166 min
2759 independent reflections	intensity decay: 9%

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.125	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.0499P)² + 0.1997P] where P = (F_o² + 2F_c²)/3
2759 reflections	(Δ/σ)_max < 0.001
177 parameters	Δρ_max = 0.16 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₅H₁₉ClO₃	γ = 74.02 (3)°
M_r = 282.75	V = 786.3 (4) Å³
Triclinic, P1	Z = 2
a = 8.601 (3) Å	Mo Kα radiation
b = 9.214 (2) Å	µ = 0.24 mm⁻¹
c = 11.033 (2) Å	T = 291 K
α = 72.67 (2)°	0.30 × 0.30 × 0.30 mm
β = 74.62 (2)°

Data collection top

Enraf–Nonius TurboCAD-4 diffractometer	1589 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.020
T_min = 0.905, T_max = 0.929	3 standard reflections every 166 min
2961 measured reflections	intensity decay: 9%
2759 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	0 restraints
wR(F²) = 0.125	H-atom parameters constrained
S = 1.01	Δρ_max = 0.16 e Å⁻³
2759 reflections	Δρ_min = −0.17 e Å⁻³
177 parameters

Special details top

Experimental. Number of psi-scan sets used was 3. Theta correction was applied. Averaged transmission function was used. No Fourier smoothing was applied.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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

	x	y	z	U_iso*/U_eq
Cl1	0.16763 (12)	0.07087 (11)	0.34258 (10)	0.1148 (4)
C1	0.0088 (3)	0.2115 (3)	0.2795 (3)	0.0715 (8)
C2	0.0200 (4)	0.2567 (3)	0.1470 (3)	0.0732 (8)
H2	0.112	0.2139	0.0922	0.088*
C3	−0.1066 (3)	0.3656 (3)	0.0975 (3)	0.0652 (7)
H3	−0.0996	0.3952	0.0083	0.078*
C4	−0.2453 (3)	0.4331 (3)	0.1768 (2)	0.0539 (6)
C5	−0.2524 (3)	0.3851 (3)	0.3101 (2)	0.0616 (7)
H5	−0.3433	0.4288	0.3654	0.074*
C6	−0.1270 (4)	0.2740 (3)	0.3615 (3)	0.0733 (8)
H6	−0.1341	0.2417	0.4507	0.088*
C7	−0.3731 (3)	0.5568 (3)	0.1130 (2)	0.0567 (6)
O1	−0.3574 (2)	0.5870 (2)	−0.00407 (18)	0.0818 (6)
C8	−0.5234 (3)	0.6450 (3)	0.1932 (2)	0.0580 (7)
C9	−0.6140 (4)	0.7842 (4)	0.1003 (3)	0.0858 (9)
H9A	−0.6522	0.7464	0.0436	0.129*
H9B	−0.5396	0.8509	0.0499	0.129*
H9C	−0.7065	0.8416	0.1499	0.129*
C10	−0.6413 (3)	0.5359 (4)	0.2725 (3)	0.0815 (9)
H10A	−0.6754	0.4959	0.215	0.122*
H10B	−0.7364	0.5926	0.3205	0.122*
H10C	−0.5855	0.451	0.3316	0.122*
C11	−0.4693 (3)	0.7139 (3)	0.2811 (3)	0.0557 (6)
O2	−0.5376 (2)	0.7174 (2)	0.39021 (18)	0.0768 (6)
O3	−0.3370 (2)	0.77357 (18)	0.21611 (15)	0.0573 (5)
C12	−0.2559 (3)	0.8503 (3)	0.2752 (3)	0.0652 (7)
C13	−0.1158 (4)	0.8952 (4)	0.1653 (3)	0.0982 (11)
H13A	−0.1601	0.9655	0.0928	0.147*
H13B	−0.0465	0.8035	0.14	0.147*
H13C	−0.052	0.945	0.1934	0.147*
C14	−0.3741 (4)	0.9938 (4)	0.3095 (4)	0.1056 (12)
H14A	−0.4215	1.0563	0.2361	0.158*
H14B	−0.3158	1.053	0.3331	0.158*
H14C	−0.4602	0.9636	0.381	0.158*
C15	−0.1904 (5)	0.7350 (4)	0.3885 (3)	0.1139 (13)
H15A	−0.2809	0.7124	0.4587	0.171*
H15B	−0.1196	0.7781	0.4159	0.171*
H15C	−0.129	0.6409	0.3633	0.171*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0975 (7)	0.1088 (7)	0.1345 (8)	0.0243 (5)	−0.0444 (6)	−0.0478 (6)
C1	0.0677 (18)	0.0628 (18)	0.088 (2)	−0.0045 (14)	−0.0202 (16)	−0.0288 (16)
C2	0.0654 (18)	0.0720 (19)	0.080 (2)	−0.0162 (16)	0.0064 (16)	−0.0313 (16)
C3	0.0745 (19)	0.0649 (17)	0.0575 (16)	−0.0239 (15)	0.0015 (15)	−0.0214 (14)
C4	0.0614 (15)	0.0556 (15)	0.0498 (14)	−0.0241 (13)	−0.0005 (12)	−0.0191 (12)
C5	0.0671 (17)	0.0592 (16)	0.0559 (16)	−0.0098 (14)	−0.0034 (13)	−0.0213 (13)
C6	0.084 (2)	0.0683 (18)	0.0657 (17)	−0.0017 (16)	−0.0181 (16)	−0.0243 (15)
C7	0.0618 (17)	0.0631 (16)	0.0541 (16)	−0.0303 (14)	−0.0073 (13)	−0.0156 (13)
O1	0.0877 (14)	0.1077 (16)	0.0519 (12)	−0.0260 (12)	−0.0120 (10)	−0.0194 (11)
C8	0.0535 (15)	0.0655 (16)	0.0594 (15)	−0.0163 (13)	−0.0123 (12)	−0.0171 (13)
C9	0.081 (2)	0.093 (2)	0.090 (2)	−0.0075 (17)	−0.0387 (18)	−0.0230 (18)
C10	0.0607 (18)	0.104 (2)	0.090 (2)	−0.0384 (17)	0.0024 (15)	−0.0343 (18)
C11	0.0538 (15)	0.0572 (16)	0.0549 (16)	−0.0106 (13)	−0.0100 (13)	−0.0139 (12)
O2	0.0796 (13)	0.0971 (15)	0.0575 (12)	−0.0311 (11)	0.0045 (10)	−0.0289 (10)
O3	0.0587 (10)	0.0672 (11)	0.0543 (10)	−0.0232 (9)	−0.0074 (8)	−0.0217 (8)
C12	0.0684 (17)	0.0764 (18)	0.0660 (17)	−0.0271 (15)	−0.0107 (14)	−0.0314 (15)
C13	0.090 (2)	0.122 (3)	0.105 (3)	−0.058 (2)	0.0055 (19)	−0.049 (2)
C14	0.096 (3)	0.102 (3)	0.145 (3)	−0.026 (2)	−0.008 (2)	−0.077 (2)
C15	0.131 (3)	0.137 (3)	0.100 (3)	−0.054 (3)	−0.063 (2)	−0.009 (2)

Geometric parameters (Å, º) top

Cl1—C1	1.739 (3)	C9—H9C	0.96
C1—C6	1.376 (4)	C10—H10A	0.96
C1—C2	1.380 (4)	C10—H10B	0.96
C2—C3	1.370 (4)	C10—H10C	0.96
C2—H2	0.93	C11—O2	1.197 (3)
C3—C4	1.392 (3)	C11—O3	1.337 (3)
C3—H3	0.93	O3—C12	1.483 (3)
C4—C5	1.394 (3)	C12—C15	1.504 (4)
C4—C7	1.498 (4)	C12—C14	1.509 (4)
C5—C6	1.380 (4)	C12—C13	1.515 (4)
C5—H5	0.93	C13—H13A	0.96
C6—H6	0.93	C13—H13B	0.96
C7—O1	1.216 (3)	C13—H13C	0.96
C7—C8	1.536 (3)	C14—H14A	0.96
C8—C11	1.526 (3)	C14—H14B	0.96
C8—C10	1.540 (4)	C14—H14C	0.96
C8—C9	1.546 (4)	C15—H15A	0.96
C9—H9A	0.96	C15—H15B	0.96
C9—H9B	0.96	C15—H15C	0.96

C6—C1—C2	120.9 (3)	C8—C10—H10B	109.5
C6—C1—Cl1	120.0 (2)	H10A—C10—H10B	109.5
C2—C1—Cl1	119.0 (2)	C8—C10—H10C	109.5
C3—C2—C1	119.0 (3)	H10A—C10—H10C	109.5
C3—C2—H2	120.5	H10B—C10—H10C	109.5
C1—C2—H2	120.5	O2—C11—O3	125.4 (2)
C2—C3—C4	122.0 (3)	O2—C11—C8	125.1 (2)
C2—C3—H3	119	O3—C11—C8	109.5 (2)
C4—C3—H3	119	C11—O3—C12	122.39 (19)
C3—C4—C5	117.5 (3)	O3—C12—C15	109.6 (2)
C3—C4—C7	117.9 (2)	O3—C12—C14	109.8 (2)
C5—C4—C7	124.5 (2)	C15—C12—C14	113.7 (3)
C6—C5—C4	121.1 (2)	O3—C12—C13	101.9 (2)
C6—C5—H5	119.4	C15—C12—C13	110.8 (3)
C4—C5—H5	119.4	C14—C12—C13	110.4 (3)
C1—C6—C5	119.4 (3)	C12—C13—H13A	109.5
C1—C6—H6	120.3	C12—C13—H13B	109.5
C5—C6—H6	120.3	H13A—C13—H13B	109.5
O1—C7—C4	119.2 (2)	C12—C13—H13C	109.5
O1—C7—C8	119.7 (2)	H13A—C13—H13C	109.5
C4—C7—C8	121.1 (2)	H13B—C13—H13C	109.5
C11—C8—C7	110.7 (2)	C12—C14—H14A	109.5
C11—C8—C10	111.1 (2)	C12—C14—H14B	109.5
C7—C8—C10	110.0 (2)	H14A—C14—H14B	109.5
C11—C8—C9	106.4 (2)	C12—C14—H14C	109.5
C7—C8—C9	109.0 (2)	H14A—C14—H14C	109.5
C10—C8—C9	109.7 (2)	H14B—C14—H14C	109.5
C8—C9—H9A	109.5	C12—C15—H15A	109.5
C8—C9—H9B	109.5	C12—C15—H15B	109.5
H9A—C9—H9B	109.5	H15A—C15—H15B	109.5
C8—C9—H9C	109.5	C12—C15—H15C	109.5
H9A—C9—H9C	109.5	H15A—C15—H15C	109.5
H9B—C9—H9C	109.5	H15B—C15—H15C	109.5
C8—C10—H10A	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10A···O1ⁱ	0.96	2.58	3.476 (4)	155
C5—H5···O2ⁱⁱ	0.93	2.7	3.316 (3)	125

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₉ClO₃
M_r	282.75
Crystal system, space group	Triclinic, P1
Temperature (K)	291
a, b, c (Å)	8.601 (3), 9.214 (2), 11.033 (2)
α, β, γ (°)	72.67 (2), 74.62 (2), 74.02 (3)
V (Å³)	786.3 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.24
Crystal size (mm)	0.30 × 0.30 × 0.30

Data collection
Diffractometer	Enraf–Nonius TurboCAD-4
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.905, 0.929
No. of measured, independent and observed [I > 2σ(I)] reflections	2961, 2759, 1589
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.125, 1.01
No. of reflections	2759
No. of parameters	177
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.16, −0.17

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SIR2004 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2008), WinGX (Farrugia, 1999) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10A···O1ⁱ	0.96	2.58	3.476 (4)	154.7
C5—H5···O2ⁱⁱ	0.93	2.7	3.316 (3)	124.9

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

Acknowledgements

Financial assistance from the Chemistry Department of Michigan Technological University is acknowledged.

References

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