tert-Butyl­ammonium 2,3,4,5-tetra­chloro-6-methoxy­carbonyl­benzoate

Li, J.; Liang, Z.-P.; Lin, C.-H.; Tai, X.-S.

doi:10.1107/S1600536808036398

organic compounds

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ISSN: 2056-9890

Volume 64| Part 12| December 2008| Page o2318

doi:10.1107/S1600536808036398

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tert-Butylammonium 2,3,4,5-tetrachloro-6-methoxycarbonylbenzoate

Jian Li,^a ^* Zu-Pei Liang,^a Cui-Hua Lin ^a and Xi-Shi Tai ^a

^aDepartment of Chemistry and Chemical Engineering, Weifang University, Weifang 261061, People's Republic of China
^*Correspondence e-mail: zupeiliang@163.com

(Received 3 September 2008; accepted 6 November 2008; online 13 November 2008)

In the title compound, C₄H₁₂N⁺·C₉H₃Cl₄O₄⁻, the benzene ring forms dihedral angles of 62.4 (2) and 64.0 (3)°, respectively, with the essentially planar methoxycarbonyl and carboxylate groups. In the crystal structure, intermolecular N—H⋯O hydrogen bonds connect anions and cations, forming one-dimensional chains along [010].

Related literature

For background information, see: Ungwitayatorn et al. (2001 ). For bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₄H₁₂N⁺·C₉H₃Cl₄O₄⁻
M_r = 391.06
Monoclinic, P 2₁
a = 9.0193 (14) Å
b = 6.5084 (11) Å
c = 14.5965 (15) Å
β = 91.7570 (10)°
V = 856.4 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.70 mm⁻¹
T = 298 (2) K
0.53 × 0.48 × 0.44 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.706, T_max = 0.747
4281 measured reflections
2790 independent reflections
2364 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.116
S = 1.04
2790 reflections
205 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.28 e Å⁻³
Absolute structure: Flack (1983 ), 1147 Friedel pairs
Flack parameter: 0.00 (9)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O4ⁱ	0.89	1.97	2.838 (4)	165
N1—H1B⋯O4ⁱⁱ	0.89	1.97	2.850 (4)	168
N1—H1C⋯O3ⁱⁱⁱ	0.89	1.94	2.818 (4)	169
Symmetry codes: (i) $[-x+1, y+{\script{1\over 2}}, -z+1]$ ; (ii) x+1, y, z; (iii) $[-x+1, y-{\script{1\over 2}}, -z+1]$ .

Data collection: SMART (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808036398/lh2693sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808036398/lh2693Isup2.hkl

checkCIF report

Comment top

Phthalimides are compounds which can posses biological activity (see: e.g. Ungwitayatorn et al., 2001). 2-(Methoxycarbonyl)-3,4,5,6-tetrachlorobenzoic acid is an intermediate in the sysnthesis of tetrachlorophthalimides and their derivatives. In this paper, the structure of the title compound (I) is reported. The asymmetric unit contains one tert-butylammonium cation and one 2-(methoxycarbonyl)-3,4,5,6-tetrachlorobenzene-1-carboxylate anion (Fig. 1). The bond lengths in (I) are normal (Allen et al., 1987). In the crystal structure, intermolecular N-H···O hydrogen bonds connect anions and cations to form one-dimensional chains along [O10].

Related literature top

For background information, see: Ungwitayatorn et al. (2001). For bond-length data, see: Allen et al. (1987).

Experimental top

A mixture of tetrachlorophthalic anhydride (2.86 g, 0.01 mol) and methanol (20 ml) was refluxed for 0.5 h and then tert-butylamine (0.73 g, 0.01 mol) was added and the mixture stirred for 4 h at room temperature. After filtration, the filtrate was kept at room temperature for 5 d. Natural evaporation gave colourless single crystals of the title compound, suitable for X-ray analysis.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of (I), drawn with 30% probability ellipsoids.
	Fig. 2. Part of the crystal structure of (I) with hydrogen bonds indicated by dashed lines.

tert-Butylammonium 2,3,4,5-tetrachloro-6-methoxycarbonylbenzoate top

Crystal data top

C₄H₁₂N⁺·C₉H₃Cl₄O₄⁻	F(000) = 400
M_r = 391.06	D_x = 1.516 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 2177 reflections
a = 9.0193 (14) Å	θ = 2.3–27.0°
b = 6.5084 (11) Å	µ = 0.71 mm⁻¹
c = 14.5965 (15) Å	T = 298 K
β = 91.757 (1)°	Block, colorless
V = 856.4 (2) Å³	0.53 × 0.48 × 0.44 mm
Z = 2

Data collection top

Bruker SMART CCD diffractometer	2790 independent reflections
Radiation source: fine-focus sealed tube	2364 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
T_min = 0.706, T_max = 0.747	k = −7→7
4281 measured reflections	l = −15→17

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.044	w = 1/[σ²(F_o²) + (0.048P)² + 0.2322P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.116	(Δ/σ)_max < 0.001
S = 1.04	Δρ_max = 0.21 e Å⁻³
2790 reflections	Δρ_min = −0.28 e Å⁻³
205 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.075 (5)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1147 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.00 (9)

Crystal data top

C₄H₁₂N⁺·C₉H₃Cl₄O₄⁻	V = 856.4 (2) Å³
M_r = 391.06	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 9.0193 (14) Å	µ = 0.71 mm⁻¹
b = 6.5084 (11) Å	T = 298 K
c = 14.5965 (15) Å	0.53 × 0.48 × 0.44 mm
β = 91.757 (1)°

Data collection top

Bruker SMART CCD diffractometer	2790 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2364 reflections with I > 2σ(I)
T_min = 0.706, T_max = 0.747	R_int = 0.043
4281 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	H-atom parameters constrained
wR(F²) = 0.116	Δρ_max = 0.21 e Å⁻³
S = 1.04	Δρ_min = −0.28 e Å⁻³
2790 reflections	Absolute structure: Flack (1983), 1147 Friedel pairs
205 parameters	Absolute structure parameter: 0.00 (9)
1 restraint

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

	x	y	z	U_iso*/U_eq
Cl1	−0.17713 (11)	0.5505 (2)	0.24305 (8)	0.0650 (4)
Cl2	−0.10033 (15)	0.2412 (2)	0.09021 (8)	0.0730 (4)
Cl3	0.20894 (14)	0.2526 (2)	0.00306 (8)	0.0670 (4)
Cl4	0.44428 (12)	0.5681 (2)	0.07197 (8)	0.0645 (4)
N1	0.9054 (3)	0.8116 (5)	0.5564 (2)	0.0332 (7)
H1A	0.9244	0.9328	0.5825	0.050*
H1B	0.9627	0.7954	0.5084	0.050*
H1C	0.9241	0.7119	0.5969	0.050*
O1	0.4059 (3)	0.9677 (5)	0.1703 (2)	0.0561 (8)
O2	0.4110 (3)	0.8206 (5)	0.30813 (19)	0.0555 (8)
O3	0.0729 (3)	1.0097 (4)	0.30549 (18)	0.0462 (7)
O4	0.0532 (3)	0.7277 (4)	0.39073 (15)	0.0375 (6)
C1	0.2425 (4)	0.6942 (6)	0.1932 (2)	0.0347 (9)
C2	0.1041 (4)	0.6869 (6)	0.2345 (2)	0.0323 (8)
C3	−0.0013 (4)	0.5489 (7)	0.1999 (2)	0.0375 (9)
C4	0.0307 (5)	0.4133 (7)	0.1295 (3)	0.0431 (10)
C5	0.1686 (5)	0.4186 (7)	0.0903 (2)	0.0408 (9)
C6	0.2727 (4)	0.5608 (7)	0.1215 (2)	0.0380 (9)
C7	0.3626 (4)	0.8340 (6)	0.2319 (3)	0.0378 (9)
C8	0.0731 (4)	0.8226 (6)	0.3175 (2)	0.0305 (8)
C9	0.5402 (5)	1.0814 (9)	0.1945 (4)	0.0701 (15)
H9A	0.6216	0.9874	0.2027	0.105*
H9B	0.5265	1.1554	0.2505	0.105*
H9C	0.5614	1.1766	0.1464	0.105*
C10	0.7440 (4)	0.8028 (6)	0.5251 (3)	0.0367 (9)
C11	0.7195 (5)	0.9690 (7)	0.4533 (3)	0.0511 (11)
H11A	0.7391	1.1011	0.4804	0.077*
H11B	0.6186	0.9642	0.4305	0.077*
H11C	0.7852	0.9469	0.4038	0.077*
C12	0.7164 (4)	0.5891 (7)	0.4845 (3)	0.0469 (10)
H12A	0.7874	0.5622	0.4383	0.070*
H12B	0.6180	0.5831	0.4576	0.070*
H12C	0.7264	0.4878	0.5321	0.070*
C13	0.6520 (4)	0.8364 (7)	0.6089 (3)	0.0487 (11)
H13A	0.5497	0.8082	0.5938	0.073*
H13B	0.6622	0.9763	0.6290	0.073*
H13C	0.6859	0.7459	0.6571	0.073*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0399 (6)	0.0959 (10)	0.0596 (7)	−0.0201 (6)	0.0101 (5)	−0.0272 (7)
Cl2	0.0733 (8)	0.0769 (10)	0.0685 (8)	−0.0297 (7)	−0.0010 (6)	−0.0322 (7)
Cl3	0.0782 (8)	0.0697 (9)	0.0532 (6)	0.0129 (7)	0.0033 (5)	−0.0277 (7)
Cl4	0.0511 (6)	0.0811 (9)	0.0627 (7)	0.0029 (6)	0.0236 (5)	−0.0087 (7)
N1	0.0333 (15)	0.0302 (17)	0.0364 (16)	0.0004 (13)	0.0033 (12)	0.0002 (14)
O1	0.0603 (19)	0.059 (2)	0.0495 (17)	−0.0197 (15)	0.0029 (14)	0.0158 (15)
O2	0.0606 (18)	0.061 (2)	0.0437 (16)	−0.0225 (16)	−0.0119 (14)	0.0098 (15)
O3	0.0623 (18)	0.0323 (18)	0.0439 (15)	−0.0008 (13)	0.0001 (13)	−0.0013 (12)
O4	0.0446 (14)	0.0374 (15)	0.0308 (13)	0.0003 (13)	0.0076 (11)	−0.0008 (12)
C1	0.039 (2)	0.035 (2)	0.0301 (18)	0.0012 (16)	−0.0010 (15)	0.0053 (16)
C2	0.0373 (19)	0.034 (2)	0.0259 (17)	−0.0030 (16)	0.0004 (15)	0.0015 (15)
C3	0.0349 (19)	0.045 (2)	0.0321 (18)	−0.0021 (19)	0.0002 (14)	−0.0037 (19)
C4	0.050 (2)	0.042 (2)	0.036 (2)	−0.0076 (19)	−0.0054 (18)	−0.0059 (18)
C5	0.050 (2)	0.042 (2)	0.0309 (19)	0.0048 (19)	0.0001 (17)	−0.0057 (17)
C6	0.0403 (19)	0.045 (2)	0.0286 (17)	0.007 (2)	0.0061 (15)	0.0042 (19)
C7	0.036 (2)	0.040 (2)	0.038 (2)	−0.0019 (17)	0.0050 (17)	0.0023 (18)
C8	0.0290 (18)	0.028 (2)	0.0340 (19)	−0.0036 (16)	−0.0012 (15)	0.0000 (16)
C9	0.064 (3)	0.070 (4)	0.078 (3)	−0.032 (3)	0.022 (2)	0.003 (3)
C10	0.0268 (17)	0.033 (2)	0.050 (2)	0.0016 (16)	−0.0027 (15)	−0.0039 (18)
C11	0.045 (2)	0.050 (3)	0.057 (3)	0.007 (2)	−0.011 (2)	0.010 (2)
C12	0.039 (2)	0.042 (3)	0.059 (3)	−0.0065 (19)	−0.0001 (18)	−0.013 (2)
C13	0.040 (2)	0.045 (3)	0.062 (3)	0.006 (2)	0.0158 (19)	−0.007 (2)

Geometric parameters (Å, º) top

Cl1—C3	1.724 (4)	C3—C4	1.392 (6)
Cl2—C4	1.714 (4)	C4—C5	1.385 (6)
Cl3—C5	1.718 (4)	C5—C6	1.385 (6)
Cl4—C6	1.729 (4)	C9—H9A	0.9600
N1—C10	1.513 (5)	C9—H9B	0.9600
N1—H1A	0.8900	C9—H9C	0.9600
N1—H1B	0.8900	C10—C13	1.515 (5)
N1—H1C	0.8900	C10—C11	1.517 (6)
O1—C7	1.319 (5)	C10—C12	1.529 (6)
O1—C9	1.455 (5)	C11—H11A	0.9600
O2—C7	1.186 (4)	C11—H11B	0.9600
O3—C8	1.230 (5)	C11—H11C	0.9600
O4—C8	1.252 (4)	C12—H12A	0.9600
C1—C6	1.394 (5)	C12—H12B	0.9600
C1—C2	1.404 (5)	C12—H12C	0.9600
C1—C7	1.511 (5)	C13—H13A	0.9600
C2—C3	1.391 (5)	C13—H13B	0.9600
C2—C8	1.532 (5)	C13—H13C	0.9600

C10—N1—H1A	109.5	O1—C9—H9A	109.5
C10—N1—H1B	109.5	O1—C9—H9B	109.5
H1A—N1—H1B	109.5	H9A—C9—H9B	109.5
C10—N1—H1C	109.5	O1—C9—H9C	109.5
H1A—N1—H1C	109.5	H9A—C9—H9C	109.5
H1B—N1—H1C	109.5	H9B—C9—H9C	109.5
C7—O1—C9	115.6 (3)	N1—C10—C13	107.2 (3)
C6—C1—C2	119.9 (3)	N1—C10—C11	107.5 (3)
C6—C1—C7	120.1 (3)	C13—C10—C11	112.5 (3)
C2—C1—C7	119.7 (3)	N1—C10—C12	107.2 (3)
C3—C2—C1	118.2 (3)	C13—C10—C12	110.9 (4)
C3—C2—C8	121.3 (3)	C11—C10—C12	111.2 (3)
C1—C2—C8	120.5 (3)	C10—C11—H11A	109.5
C2—C3—C4	121.5 (3)	C10—C11—H11B	109.5
C2—C3—Cl1	119.3 (3)	H11A—C11—H11B	109.5
C4—C3—Cl1	119.1 (3)	C10—C11—H11C	109.5
C5—C4—C3	119.8 (4)	H11A—C11—H11C	109.5
C5—C4—Cl2	119.8 (3)	H11B—C11—H11C	109.5
C3—C4—Cl2	120.3 (3)	C10—C12—H12A	109.5
C6—C5—C4	119.3 (4)	C10—C12—H12B	109.5
C6—C5—Cl3	120.4 (3)	H12A—C12—H12B	109.5
C4—C5—Cl3	120.2 (3)	C10—C12—H12C	109.5
C5—C6—C1	121.1 (3)	H12A—C12—H12C	109.5
C5—C6—Cl4	119.2 (3)	H12B—C12—H12C	109.5
C1—C6—Cl4	119.7 (3)	C10—C13—H13A	109.5
O2—C7—O1	125.4 (4)	C10—C13—H13B	109.5
O2—C7—C1	123.1 (4)	H13A—C13—H13B	109.5
O1—C7—C1	111.5 (3)	C10—C13—H13C	109.5
O3—C8—O4	127.6 (3)	H13A—C13—H13C	109.5
O3—C8—C2	117.2 (3)	H13B—C13—H13C	109.5
O4—C8—C2	115.2 (3)

C6—C1—C2—C3	−2.0 (5)	Cl3—C5—C6—C1	−179.0 (3)
C7—C1—C2—C3	−176.8 (3)	C4—C5—C6—Cl4	−179.6 (3)
C6—C1—C2—C8	175.9 (3)	Cl3—C5—C6—Cl4	−0.5 (5)
C7—C1—C2—C8	1.2 (5)	C2—C1—C6—C5	−0.5 (5)
C1—C2—C3—C4	3.3 (6)	C7—C1—C6—C5	174.2 (4)
C8—C2—C3—C4	−174.6 (4)	C2—C1—C6—Cl4	−179.1 (3)
C1—C2—C3—Cl1	−174.8 (3)	C7—C1—C6—Cl4	−4.3 (5)
C8—C2—C3—Cl1	7.3 (5)	C9—O1—C7—O2	11.0 (6)
C2—C3—C4—C5	−2.0 (6)	C9—O1—C7—C1	−168.3 (4)
Cl1—C3—C4—C5	176.1 (3)	C6—C1—C7—O2	−115.3 (4)
C2—C3—C4—Cl2	178.5 (3)	C2—C1—C7—O2	59.4 (5)
Cl1—C3—C4—Cl2	−3.4 (5)	C6—C1—C7—O1	64.0 (5)
C3—C4—C5—C6	−0.6 (6)	C2—C1—C7—O1	−121.3 (4)
Cl2—C4—C5—C6	178.8 (3)	C3—C2—C8—O3	−117.6 (4)
C3—C4—C5—Cl3	−179.8 (3)	C1—C2—C8—O3	64.5 (5)
Cl2—C4—C5—Cl3	−0.3 (5)	C3—C2—C8—O4	63.6 (5)
C4—C5—C6—C1	1.9 (6)	C1—C2—C8—O4	−114.3 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4ⁱ	0.89	1.97	2.838 (4)	165
N1—H1B···O4ⁱⁱ	0.89	1.97	2.850 (4)	168
N1—H1C···O3ⁱⁱⁱ	0.89	1.94	2.818 (4)	169

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

Experimental details

Crystal data
Chemical formula	C₄H₁₂N⁺·C₉H₃Cl₄O₄⁻
M_r	391.06
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	298
a, b, c (Å)	9.0193 (14), 6.5084 (11), 14.5965 (15)
β (°)	91.757 (1)
V (Å³)	856.4 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.71
Crystal size (mm)	0.53 × 0.48 × 0.44

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.706, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	4281, 2790, 2364
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.116, 1.04
No. of reflections	2790
No. of parameters	205
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.28
Absolute structure	Flack (1983), 1147 Friedel pairs
Absolute structure parameter	0.00 (9)

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4ⁱ	0.89	1.97	2.838 (4)	165
N1—H1B···O4ⁱⁱ	0.89	1.97	2.850 (4)	168
N1—H1C···O3ⁱⁱⁱ	0.89	1.94	2.818 (4)	169

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

Acknowledgements

This work was supported by the Natural Science Foundation of Shandong Province (No. Y2007B61).

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