Tetra­methyl 4,4′-carbonyl­bis(benzene-1,2-dicarboxyl­ate)

Zhu, X.-Y.; Gao, G.-W.; Men, J.; Ng, S.W.

doi:10.1107/S1600536809009271

organic compounds

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Volume 65| Part 4| April 2009| Page o794

doi:10.1107/S1600536809009271

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Tetramethyl 4,4′-carbonylbis(benzene-1,2-dicarboxylate)

Xin-Yi Zhu,^a Guo-Wei Gao,^a Jian Men ^a and Seik Weng Ng ^b ^*

^aCollege of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China, and ^bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 11 March 2009; accepted 13 March 2009; online 19 March 2009)

In the molecule of the title compound, C₂₁H₁₈O₉, the two aromatic rings are aligned at an angle of 49.7 (1)°.

Related literature

For the parent acid monohydrate, see: Fitzgerald & Gerkin (1997 ). For related literature, see: Zhang et al. (2004 ).

Experimental

Crystal data

C₂₁H₁₈O₉
M_r = 414.35
Monoclinic, P 2₁ /c
a = 11.8627 (2) Å
b = 17.3678 (3) Å
c = 9.2506 (2) Å
β = 95.150 (1)°
V = 1898.20 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 123 K
0.45 × 0.15 × 0.05 mm

Data collection

Bruker SMART APEX diffractometer
Absorption correction: none
14279 measured reflections
4339 independent reflections
3596 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.139
S = 1.04
4339 reflections
275 parameters
H-atom parameters constrained
Δρ_max = 0.89 e Å⁻³
Δρ_min = −0.50 e Å⁻³

Data collection: APEX2 (Bruker, 2008 ); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809009271/tk2392sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809009271/tk2392Isup2.hkl

checkCIF report

Related literature top

For the parent acid monohydrate, see: Fitzgerald & Gerkin (1997). For related literature, see: Zhang et al. (2004).

Experimental top

3,3',4,4'-Tetracarboxybenzophenone (29.4 g, 0.1 mol) and p-toluenesulfonic acid (2.0 g, 0.01 mol) were heated in a mixture of toluene (100 ml) and methanol (50 ml) in a Dean-Stark apparatus for 20 h. Water (500 ml) was added to the mixture, the organic phase was separated and washed with saturated sodium carbonate. The toluene was removed and the product purified from ethanol to afford a white powder (34.7 g, 90% yield; m.p. 382–384 K). Colorless single crystals were obtained by recrystallization from toluene.

Computing details top

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: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of C₂₁H₁₈O₉ at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.

Tetramethyl 4,4'-carbonylbis(benzene-1,2-dicarboxylate) top

Crystal data top

C₂₁H₁₈O₉	F(000) = 864
M_r = 414.35	D_x = 1.450 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5155 reflections
a = 11.8627 (2) Å	θ = 2.9–28.2°
b = 17.3678 (3) Å	µ = 0.12 mm⁻¹
c = 9.2506 (2) Å	T = 123 K
β = 95.150 (1)°	Block, colorless
V = 1898.20 (6) Å³	0.45 × 0.15 × 0.05 mm
Z = 4

Data collection top

Bruker SMART APEX [APEXII?] diffractometer	3596 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.024
Graphite monochromator	θ_max = 27.5°, θ_min = 1.7°
ω scans	h = −15→15
14279 measured reflections	k = −22→22
4339 independent reflections	l = −11→12

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.139	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0704P)² + 1.4144P] where P = (F_o² + 2F_c²)/3
4339 reflections	(Δ/σ)_max = 0.001
275 parameters	Δρ_max = 0.89 e Å⁻³
0 restraints	Δρ_min = −0.50 e Å⁻³

Crystal data top

C₂₁H₁₈O₉	V = 1898.20 (6) Å³
M_r = 414.35	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 11.8627 (2) Å	µ = 0.12 mm⁻¹
b = 17.3678 (3) Å	T = 123 K
c = 9.2506 (2) Å	0.45 × 0.15 × 0.05 mm
β = 95.150 (1)°

Data collection top

Bruker SMART APEX [APEXII?] diffractometer	3596 reflections with I > 2σ(I)
14279 measured reflections	R_int = 0.024
4339 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	0 restraints
wR(F²) = 0.139	H-atom parameters constrained
S = 1.04	Δρ_max = 0.89 e Å⁻³
4339 reflections	Δρ_min = −0.50 e Å⁻³
275 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.82828 (10)	0.56029 (7)	0.93784 (12)	0.0205 (3)
O2	1.01037 (11)	0.56968 (8)	0.88890 (13)	0.0261 (3)
O3	0.89532 (11)	0.62457 (7)	0.42114 (13)	0.0227 (3)
O4	0.87735 (13)	0.65645 (7)	0.65258 (14)	0.0288 (3)
O5	0.47658 (11)	0.33391 (8)	0.30590 (16)	0.0310 (3)
O6	0.38426 (16)	0.22311 (10)	0.2777 (3)	0.0726 (7)
O7	0.50941 (16)	0.09165 (11)	0.19849 (17)	0.0525 (5)
O8	0.42373 (14)	0.05561 (10)	0.38926 (19)	0.0458 (4)
O9	0.85745 (11)	0.25995 (7)	0.79479 (13)	0.0236 (3)
C1	0.82935 (13)	0.36953 (9)	0.64550 (17)	0.0163 (3)
C2	0.85873 (13)	0.42065 (9)	0.75874 (17)	0.0165 (3)
H2	0.8650	0.4026	0.8561	0.020*
C3	0.87895 (13)	0.49763 (9)	0.73051 (17)	0.0160 (3)
C4	0.87127 (13)	0.52414 (9)	0.58682 (17)	0.0158 (3)
C5	0.84754 (14)	0.47205 (9)	0.47349 (17)	0.0180 (3)
H5	0.8463	0.4892	0.3759	0.022*
C6	0.82574 (14)	0.39516 (9)	0.50221 (17)	0.0177 (3)
H6	0.8084	0.3602	0.4245	0.021*
C7	0.91496 (14)	0.54819 (9)	0.85827 (17)	0.0173 (3)
C8	0.85333 (17)	0.60385 (11)	1.07015 (19)	0.0262 (4)
H8A	0.7826	0.6222	1.1053	0.039*
H8B	0.9012	0.6480	1.0508	0.039*
H8C	0.8932	0.5709	1.1440	0.039*
C9	0.88242 (14)	0.60863 (9)	0.55979 (17)	0.0170 (3)
C10	0.90221 (18)	0.70612 (10)	0.3881 (2)	0.0280 (4)
H10A	0.8282	0.7302	0.3952	0.042*
H10B	0.9246	0.7126	0.2894	0.042*
H10C	0.9585	0.7306	0.4573	0.042*
C11	0.72742 (14)	0.23959 (9)	0.59007 (17)	0.0168 (3)
C12	0.63715 (14)	0.27188 (9)	0.50347 (18)	0.0187 (3)
H12	0.6268	0.3261	0.5024	0.022*
C13	0.56220 (14)	0.22528 (10)	0.41868 (19)	0.0210 (4)
C14	0.57621 (15)	0.14533 (10)	0.42228 (19)	0.0220 (4)
C15	0.66549 (15)	0.11274 (10)	0.50977 (19)	0.0223 (4)
H15	0.6748	0.0584	0.5127	0.027*
C16	0.74083 (14)	0.15960 (9)	0.59265 (18)	0.0189 (3)
H16	0.8019	0.1372	0.6515	0.023*
C17	0.46489 (16)	0.25921 (11)	0.3262 (2)	0.0287 (4)
C18	0.38474 (18)	0.37057 (13)	0.2166 (2)	0.0354 (5)
H18A	0.3787	0.3477	0.1194	0.053*
H18B	0.4001	0.4258	0.2094	0.053*
H18C	0.3136	0.3629	0.2609	0.053*
C19	0.49327 (17)	0.09303 (11)	0.3372 (2)	0.0300 (4)
C20	0.4158 (3)	0.0543 (2)	0.1117 (3)	0.0687 (9)
H20A	0.4090	0.0008	0.1436	0.103*
H20B	0.4303	0.0552	0.0091	0.103*
H20C	0.3452	0.0819	0.1242	0.103*
C21	0.80855 (14)	0.28732 (9)	0.68492 (17)	0.0172 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0222 (6)	0.0240 (6)	0.0151 (5)	0.0013 (5)	−0.0003 (4)	−0.0048 (5)
O2	0.0248 (7)	0.0309 (7)	0.0223 (6)	−0.0094 (5)	0.0005 (5)	−0.0043 (5)
O3	0.0370 (7)	0.0143 (6)	0.0168 (6)	−0.0020 (5)	0.0027 (5)	0.0017 (4)
O4	0.0485 (9)	0.0173 (6)	0.0217 (6)	−0.0032 (6)	0.0094 (6)	−0.0037 (5)
O5	0.0251 (7)	0.0254 (7)	0.0403 (8)	0.0007 (5)	−0.0099 (6)	0.0103 (6)
O6	0.0480 (11)	0.0316 (9)	0.1273 (19)	−0.0056 (8)	−0.0526 (12)	0.0061 (10)
O7	0.0661 (12)	0.0602 (11)	0.0298 (8)	−0.0355 (9)	−0.0036 (8)	−0.0023 (7)
O8	0.0378 (9)	0.0433 (9)	0.0561 (10)	−0.0220 (7)	0.0039 (7)	−0.0106 (8)
O9	0.0298 (7)	0.0194 (6)	0.0205 (6)	−0.0013 (5)	−0.0032 (5)	0.0045 (5)
C1	0.0158 (7)	0.0157 (7)	0.0171 (7)	0.0003 (6)	0.0003 (6)	0.0000 (6)
C2	0.0172 (8)	0.0178 (8)	0.0141 (7)	−0.0019 (6)	−0.0004 (6)	0.0013 (6)
C3	0.0149 (7)	0.0177 (8)	0.0154 (7)	−0.0014 (6)	0.0007 (6)	−0.0014 (6)
C4	0.0158 (7)	0.0157 (7)	0.0160 (7)	−0.0004 (6)	0.0010 (6)	0.0004 (6)
C5	0.0222 (8)	0.0180 (8)	0.0137 (7)	−0.0007 (6)	0.0016 (6)	0.0014 (6)
C6	0.0215 (8)	0.0164 (8)	0.0150 (7)	−0.0006 (6)	0.0001 (6)	−0.0030 (6)
C7	0.0215 (8)	0.0159 (7)	0.0140 (7)	−0.0020 (6)	−0.0006 (6)	0.0018 (6)
C8	0.0336 (10)	0.0275 (9)	0.0173 (8)	0.0032 (7)	−0.0001 (7)	−0.0071 (7)
C9	0.0172 (8)	0.0167 (7)	0.0169 (7)	−0.0003 (6)	0.0007 (6)	0.0001 (6)
C10	0.0433 (11)	0.0146 (8)	0.0260 (9)	−0.0018 (7)	0.0029 (8)	0.0046 (7)
C11	0.0185 (8)	0.0154 (7)	0.0168 (8)	−0.0009 (6)	0.0033 (6)	−0.0005 (6)
C12	0.0186 (8)	0.0145 (7)	0.0231 (8)	0.0004 (6)	0.0032 (6)	0.0013 (6)
C13	0.0186 (8)	0.0186 (8)	0.0257 (9)	−0.0006 (6)	0.0018 (7)	0.0018 (6)
C14	0.0203 (8)	0.0187 (8)	0.0270 (9)	−0.0035 (6)	0.0013 (7)	−0.0009 (7)
C15	0.0260 (9)	0.0142 (8)	0.0266 (9)	−0.0009 (6)	0.0028 (7)	−0.0003 (6)
C16	0.0208 (8)	0.0163 (8)	0.0197 (8)	0.0010 (6)	0.0021 (6)	0.0027 (6)
C17	0.0234 (9)	0.0232 (9)	0.0377 (11)	0.0000 (7)	−0.0063 (8)	0.0000 (8)
C18	0.0290 (10)	0.0345 (11)	0.0404 (11)	0.0064 (8)	−0.0097 (9)	0.0107 (9)
C19	0.0344 (11)	0.0194 (9)	0.0345 (10)	−0.0007 (7)	−0.0072 (8)	−0.0004 (8)
C20	0.076 (2)	0.084 (2)	0.0432 (15)	−0.0364 (17)	−0.0131 (14)	−0.0089 (14)
C21	0.0191 (8)	0.0162 (8)	0.0164 (7)	0.0001 (6)	0.0031 (6)	0.0006 (6)

Geometric parameters (Å, º) top

O1—C7	1.334 (2)	C8—H8A	0.9800
O1—C8	1.447 (2)	C8—H8B	0.9800
O2—C7	1.201 (2)	C8—H8C	0.9800
O3—C9	1.334 (2)	C10—H10A	0.9800
O3—C10	1.453 (2)	C10—H10B	0.9800
O4—C9	1.200 (2)	C10—H10C	0.9800
O5—C17	1.320 (2)	C11—C16	1.398 (2)
O5—C18	1.454 (2)	C11—C12	1.396 (2)
O6—C17	1.197 (2)	C11—C21	1.494 (2)
O7—C19	1.315 (3)	C12—C13	1.391 (2)
O7—C20	1.463 (3)	C12—H12	0.9500
O8—C19	1.186 (3)	C13—C14	1.399 (2)
O9—C21	1.220 (2)	C13—C17	1.495 (2)
C1—C2	1.393 (2)	C14—C15	1.394 (2)
C1—C6	1.395 (2)	C14—C19	1.508 (2)
C1—C21	1.500 (2)	C15—C16	1.388 (2)
C2—C3	1.387 (2)	C15—H15	0.9500
C2—H2	0.9500	C16—H16	0.9500
C3—C4	1.402 (2)	C18—H18A	0.9800
C3—C7	1.503 (2)	C18—H18B	0.9800
C4—C5	1.394 (2)	C18—H18C	0.9800
C4—C9	1.496 (2)	C20—H20A	0.9800
C5—C6	1.390 (2)	C20—H20B	0.9800
C5—H5	0.9500	C20—H20C	0.9800
C6—H6	0.9500

C7—O1—C8	116.05 (14)	C16—C11—C12	119.28 (15)
C9—O3—C10	114.72 (13)	C16—C11—C21	118.36 (15)
C17—O5—C18	115.37 (15)	C12—C11—C21	122.33 (14)
C19—O7—C20	111.96 (19)	C13—C12—C11	120.56 (15)
C2—C1—C6	119.69 (15)	C13—C12—H12	119.7
C2—C1—C21	117.35 (14)	C11—C12—H12	119.7
C6—C1—C21	122.89 (14)	C12—C13—C14	119.71 (16)
C3—C2—C1	120.55 (14)	C12—C13—C17	121.00 (15)
C3—C2—H2	119.7	C14—C13—C17	119.28 (16)
C1—C2—H2	119.7	C15—C14—C13	119.97 (16)
C2—C3—C4	119.83 (14)	C15—C14—C19	118.98 (15)
C2—C3—C7	117.18 (14)	C13—C14—C19	121.01 (16)
C4—C3—C7	122.91 (14)	C16—C15—C14	120.04 (15)
C5—C4—C3	119.43 (14)	C16—C15—H15	120.0
C5—C4—C9	121.71 (14)	C14—C15—H15	120.0
C3—C4—C9	118.77 (14)	C15—C16—C11	120.44 (15)
C6—C5—C4	120.53 (14)	C15—C16—H16	119.8
C6—C5—H5	119.7	C11—C16—H16	119.8
C4—C5—H5	119.7	O6—C17—O5	123.51 (18)
C5—C6—C1	119.84 (14)	O6—C17—C13	123.94 (18)
C5—C6—H6	120.1	O5—C17—C13	112.54 (15)
C1—C6—H6	120.1	O5—C18—H18A	109.5
O2—C7—O1	125.28 (15)	O5—C18—H18B	109.5
O2—C7—C3	124.21 (15)	H18A—C18—H18B	109.5
O1—C7—C3	110.31 (13)	O5—C18—H18C	109.5
O1—C8—H8A	109.5	H18A—C18—H18C	109.5
O1—C8—H8B	109.5	H18B—C18—H18C	109.5
H8A—C8—H8B	109.5	O8—C19—O7	123.63 (19)
O1—C8—H8C	109.5	O8—C19—C14	124.31 (19)
H8A—C8—H8C	109.5	O7—C19—C14	112.02 (17)
H8B—C8—H8C	109.5	O7—C20—H20A	109.5
O4—C9—O3	124.16 (15)	O7—C20—H20B	109.5
O4—C9—C4	123.26 (15)	H20A—C20—H20B	109.5
O3—C9—C4	112.55 (13)	O7—C20—H20C	109.5
O3—C10—H10A	109.5	H20A—C20—H20C	109.5
O3—C10—H10B	109.5	H20B—C20—H20C	109.5
H10A—C10—H10B	109.5	O9—C21—C11	120.40 (14)
O3—C10—H10C	109.5	O9—C21—C1	119.80 (15)
H10A—C10—H10C	109.5	C11—C21—C1	119.80 (13)
H10B—C10—H10C	109.5

C6—C1—C2—C3	3.2 (2)	C12—C13—C14—C15	−0.5 (3)
C21—C1—C2—C3	−179.84 (14)	C17—C13—C14—C15	−178.97 (17)
C1—C2—C3—C4	−0.8 (2)	C12—C13—C14—C19	177.06 (17)
C1—C2—C3—C7	−177.49 (15)	C17—C13—C14—C19	−1.4 (3)
C2—C3—C4—C5	−2.4 (2)	C13—C14—C15—C16	−0.4 (3)
C7—C3—C4—C5	174.02 (15)	C19—C14—C15—C16	−177.95 (17)
C2—C3—C4—C9	174.17 (14)	C14—C15—C16—C11	0.5 (3)
C7—C3—C4—C9	−9.4 (2)	C12—C11—C16—C15	0.2 (2)
C3—C4—C5—C6	3.4 (2)	C21—C11—C16—C15	178.04 (15)
C9—C4—C5—C6	−173.13 (15)	C18—O5—C17—O6	−1.2 (3)
C4—C5—C6—C1	−1.0 (2)	C18—O5—C17—C13	179.94 (17)
C2—C1—C6—C5	−2.3 (2)	C12—C13—C17—O6	−162.3 (2)
C21—C1—C6—C5	−179.05 (15)	C14—C13—C17—O6	16.2 (3)
C8—O1—C7—O2	0.9 (2)	C12—C13—C17—O5	16.6 (3)
C8—O1—C7—C3	175.88 (13)	C14—C13—C17—O5	−164.95 (17)
C2—C3—C7—O2	103.63 (19)	C20—O7—C19—O8	14.0 (3)
C4—C3—C7—O2	−72.9 (2)	C20—O7—C19—C14	−168.1 (2)
C2—C3—C7—O1	−71.44 (18)	C15—C14—C19—O8	73.0 (3)
C4—C3—C7—O1	112.03 (17)	C13—C14—C19—O8	−104.6 (2)
C10—O3—C9—O4	−0.5 (2)	C15—C14—C19—O7	−104.9 (2)
C10—O3—C9—C4	177.76 (14)	C13—C14—C19—O7	77.6 (2)
C5—C4—C9—O4	162.70 (17)	C16—C11—C21—O9	−25.3 (2)
C3—C4—C9—O4	−13.8 (2)	C12—C11—C21—O9	152.50 (16)
C5—C4—C9—O3	−15.5 (2)	C16—C11—C21—C1	155.19 (15)
C3—C4—C9—O3	167.94 (14)	C12—C11—C21—C1	−27.0 (2)
C16—C11—C12—C13	−1.0 (2)	C2—C1—C21—O9	−29.0 (2)
C21—C11—C12—C13	−178.79 (15)	C6—C1—C21—O9	147.90 (17)
C11—C12—C13—C14	1.2 (3)	C2—C1—C21—C11	150.56 (15)
C11—C12—C13—C17	179.64 (16)	C6—C1—C21—C11	−32.6 (2)

Experimental details

Crystal data
Chemical formula	C₂₁H₁₈O₉
M_r	414.35
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	123
a, b, c (Å)	11.8627 (2), 17.3678 (3), 9.2506 (2)
β (°)	95.150 (1)
V (Å³)	1898.20 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.45 × 0.15 × 0.05

Data collection
Diffractometer	Bruker SMART APEX [APEXII?] diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	14279, 4339, 3596
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.139, 1.04
No. of reflections	4339
No. of parameters	275
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.89, −0.50

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).

Acknowledgements

The authors thank the Undergraduates Innovative Experiment Project, the Experimental Technical Project of Sichuan University (grant No. 07-54) and the University of Malaya for supporting this study.

References

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