Triphenyl­methyl benzoate

Sykora, R.E.; McDonald, L.; Spyridis, G.T.

doi:10.1107/S160053680902889X

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page o2026

doi:10.1107/S160053680902889X

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Triphenylmethyl benzoate

Richard E. Sykora,^a Lane McDonald ^a and Greg T. Spyridis ^b ^*

^aDepartment of Chemistry, University of South Alabama, Mobile, AL 36688-0002, USA, and ^bDepartment of Chemistry, Seattle Pacific University, Seattle, WA 98119-1997, USA
^*Correspondence e-mail: spyrig@spu.edu

(Received 8 July 2009; accepted 21 July 2009; online 29 July 2009)

The title compound, C₂₆H₂₀O₂, has long been known, but was not structurally characterized until now. It adopts the Z conformation and the atoms comprising the ester linkage are essentially coplanar (r.m.s. deviation of 0.0234 Å). The acyl C—O bond length of 1.470 (2) Å falls within the normal range seen for esters of tertiary alcohols and is below the value of 1.496 Å found in tri-tert-butylmethyl 4-nitrobenzoate.

Related literature

For related structures of sterically hindered esters, see: phenyl benzoate (Adams & Morsi, 1976 ), a 4-substituted tert-butyl benzoate (Fu et al., 2008 ), tri-tert-butylmethyl 4-nitrobenzoate (Cheng & Nyburg, 1978 ), and for esters of tertiary alcohols, see: Allen & Kirby (1984 ); Schweizer & Dunitz (1982 ). For the synthesis, see: Blicke (1923 ) and for ionic field studies in solutions of the title compound, see: Velazquez et al. (2006 ). For additional related references on the calculated absolute structure parameter and the conformations of esters, see: (Flack, 1983 ) and Pawar et al. (1998 ).

Experimental

Crystal data

C₂₆H₂₀O₂
M_r = 364.42
Orthorhombic, P n a 2₁
a = 8.9512 (4) Å
b = 14.9545 (5) Å
c = 14.4038 (6) Å
V = 1928.10 (13) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 290 K
0.50 × 0.15 × 0.07 mm

Data collection

Oxford Diffraction Xcalibur diffractometer with an Eos CCD detector
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.959, T_max = 0.995
6656 measured reflections
2664 independent reflections
1879 reflections with I > 2σ(I)
R_int = 0.022

Refinement

R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.070
S = 0.91
2664 reflections
254 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.12 e Å⁻³
Δρ_min = −0.12 e Å⁻³

Data collection: CrysAlis Pro (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis Pro. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis Pro; data reduction: CrysAlis Pro; 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: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680902889X/zs2001sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680902889X/zs2001Isup2.hkl

checkCIF report

Comment top

In light of our investigations into the use of the title compound as a probe of the ionic fields present in LiClO₄-Et₂O solutions, (Velazquez et al., 2006), we prepared and crystallized triphenylmethyl benzoate, (I). The title compound adopts the Z-conformation (Pawar et al. 1998) with the C2—C1—O1—C8 dihedral angle being 3.5 (1)° and the phenyl ring exhibiting a slight twist of 17.6 (2)° with respect to the ester group. The atoms comprising the ester linkage, C2, C1, O2, O1 and C8, are essentially coplanar. The acyl C—O bond length of 1.470 (2) Å falls within the normal range as seen for the esters of tertiary alcohols (Allen & Kirby, 1984; Schweizer & Dunitz, 1982) and is well below the value of 1.496 Å in tri-tert-butylmethyl 4-nitrobenzoate (Cheng & Nyburg, 1978). The C1—O1—C8 bond angle is 120.50 (13)°, midway between the 118.3° observed in phenyl benzoate (Adams & Morsi, 1976) and the 122.9° seen in a 4-substituted tert-butyl benzoate (Fu et al. 2008), and is consistent with those noted for the esters of tertiary alcohols (Schweizer & Dunitz, 1982).

Related literature top

For related structures of sterically hindered esters, see: phenyl benzoate (Adams & Morsi, 1976), 4-substituted tert-butyl benzoate (Fu et al. (2008)), tri-tert-butylmethyl 4-nitrobenzoate (Cheng & Nyburg, 1978), and for esters of tertiary alcohols, see: Allen & Kirby (1984); Schweizer & Dunitz (1982). Related literature also includes the synthesis (Blicke, 1923) and ionic field studies in solutions of the title compound (Velazquez et al., 2006). For additional related references, see: (Flack, 1983) and Pawar et al. (1998).

Experimental top

The title compound was synthesized by reacting trityl chloride with silver benzoate in dry benzene as outlined in the literature (Blicke, 1923). Crystals were grown by slow evaporation from benzene at 298 K. m.p. 442.5–444.15 K.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXP97 (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

Fig. 1. The molecular structure of (I), with the atom-numbering scheme. Displacement ellipsoids for non-hydrogen atoms are drawn at the 50% probability level.

Triphenylmethyl benzoate top

Crystal data top

C₂₆H₂₀O₂	D_x = 1.255 Mg m⁻³
M_r = 364.42	Melting point = 440.5–444.5 K
Orthorhombic, Pna2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 2913 reflections
a = 8.9512 (4) Å	θ = 3.1–30.4°
b = 14.9545 (5) Å	µ = 0.08 mm⁻¹
c = 14.4038 (6) Å	T = 290 K
V = 1928.10 (13) Å³	Prism, colorless
Z = 4	0.50 × 0.15 × 0.07 mm
F(000) = 768

Data collection top

Oxford Diffraction Xcalibur diffractometer with an Eos CCD detector	2664 independent reflections
Radiation source: fine-focus sealed tube	1879 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
Detector resolution: 16.0514 pixels mm^-1	θ_max = 30.4°, θ_min = 3.6°
ω scans	h = −11→6
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −20→8
T_min = 0.959, T_max = 0.995	l = −14→20
6656 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: none
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.036	H-atom parameters constrained
wR(F²) = 0.070	w = 1/[σ²(F_o²) + (0.0394P)²] where P = (F_o² + 2F_c²)/3
S = 0.91	(Δ/σ)_max < 0.001
2664 reflections	Δρ_max = 0.12 e Å⁻³
254 parameters	Δρ_min = −0.12 e Å⁻³
1 restraint	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0067 (13)

Crystal data top

C₂₆H₂₀O₂	V = 1928.10 (13) Å³
M_r = 364.42	Z = 4
Orthorhombic, Pna2₁	Mo Kα radiation
a = 8.9512 (4) Å	µ = 0.08 mm⁻¹
b = 14.9545 (5) Å	T = 290 K
c = 14.4038 (6) Å	0.50 × 0.15 × 0.07 mm

Data collection top

Oxford Diffraction Xcalibur diffractometer with an Eos CCD detector	2664 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1879 reflections with I > 2σ(I)
T_min = 0.959, T_max = 0.995	R_int = 0.022
6656 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	1 restraint
wR(F²) = 0.070	H-atom parameters constrained
S = 0.91	Δρ_max = 0.12 e Å⁻³
2664 reflections	Δρ_min = −0.12 e Å⁻³
254 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 > 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
O1	0.09567 (13)	0.02387 (8)	0.19684 (8)	0.0377 (3)
O2	0.27149 (15)	−0.04826 (9)	0.28069 (10)	0.0513 (3)
C1	0.23123 (18)	−0.01384 (11)	0.20970 (13)	0.0364 (4)
C2	0.3253 (2)	−0.00547 (11)	0.12520 (13)	0.0389 (4)
C3	0.2950 (2)	0.05570 (13)	0.05580 (13)	0.0470 (5)
H3	0.2109	0.0920	0.0602	0.056*
C4	0.3891 (3)	0.06332 (16)	−0.02053 (15)	0.0611 (6)
H4	0.3684	0.1045	−0.0671	0.073*
C5	0.5127 (3)	0.0096 (2)	−0.02643 (17)	0.0715 (7)
H5	0.5764	0.0146	−0.0772	0.086*
C6	0.5431 (3)	−0.05147 (18)	0.0419 (2)	0.0729 (7)
H6	0.6267	−0.0881	0.0367	0.087*
C7	0.4512 (2)	−0.05927 (14)	0.11823 (16)	0.0564 (5)
H7	0.4734	−0.1003	0.1648	0.068*
C8	−0.01225 (19)	0.02868 (11)	0.27363 (12)	0.0340 (4)
C9	−0.05440 (19)	−0.06734 (11)	0.30194 (12)	0.0352 (4)
C10	−0.1514 (2)	−0.11564 (12)	0.24597 (14)	0.0486 (5)
H10	−0.1927	−0.0888	0.1937	0.058*
C11	−0.1874 (3)	−0.20348 (13)	0.26723 (17)	0.0612 (6)
H11	−0.2518	−0.2353	0.2288	0.073*
C12	−0.1287 (3)	−0.24365 (13)	0.34465 (17)	0.0589 (6)
H12	−0.1538	−0.3024	0.3591	0.071*
C13	−0.0327 (2)	−0.19667 (12)	0.40057 (16)	0.0517 (5)
H13	0.0073	−0.2239	0.4530	0.062*
C14	0.0052 (2)	−0.10936 (12)	0.37983 (14)	0.0424 (4)
H14	0.0709	−0.0784	0.4182	0.051*
C15	0.0481 (2)	0.08856 (11)	0.35106 (13)	0.0361 (4)
C16	0.1604 (2)	0.15027 (12)	0.33333 (15)	0.0480 (5)
H16	0.2058	0.1517	0.2753	0.058*
C17	0.2052 (3)	0.20958 (14)	0.40161 (19)	0.0649 (7)
H17	0.2819	0.2499	0.3894	0.078*
C18	0.1379 (3)	0.20969 (14)	0.48721 (18)	0.0672 (7)
H18	0.1681	0.2501	0.5326	0.081*
C19	0.0260 (3)	0.14994 (15)	0.50529 (16)	0.0622 (6)
H19	−0.0203	0.1500	0.5631	0.075*
C20	−0.0189 (2)	0.08948 (13)	0.43834 (13)	0.0481 (5)
H20	−0.0947	0.0489	0.4517	0.058*
C21	−0.14691 (19)	0.07741 (10)	0.23019 (12)	0.0364 (4)
C22	−0.1388 (2)	0.12181 (13)	0.14637 (15)	0.0545 (5)
H22	−0.0505	0.1205	0.1124	0.065*
C23	−0.2611 (3)	0.16830 (15)	0.11242 (19)	0.0677 (7)
H23	−0.2539	0.1981	0.0559	0.081*
C24	−0.3917 (2)	0.17089 (13)	0.1609 (2)	0.0619 (6)
H24	−0.4733	0.2022	0.1377	0.074*
C25	−0.4017 (2)	0.12700 (15)	0.24394 (18)	0.0601 (6)
H25	−0.4905	0.1284	0.2774	0.072*
C26	−0.2805 (2)	0.08062 (13)	0.27826 (16)	0.0512 (5)
H26	−0.2889	0.0510	0.3348	0.061*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0315 (6)	0.0499 (6)	0.0316 (6)	0.0018 (5)	0.0016 (5)	0.0073 (6)
O2	0.0433 (7)	0.0647 (8)	0.0459 (8)	0.0086 (6)	−0.0012 (7)	0.0170 (7)
C1	0.0318 (9)	0.0397 (8)	0.0377 (10)	−0.0005 (7)	0.0008 (8)	0.0045 (8)
C2	0.0331 (9)	0.0452 (9)	0.0385 (10)	−0.0048 (8)	−0.0011 (8)	−0.0075 (9)
C3	0.0390 (11)	0.0613 (12)	0.0407 (11)	−0.0085 (9)	−0.0003 (8)	0.0032 (10)
C4	0.0582 (15)	0.0878 (15)	0.0373 (11)	−0.0193 (12)	0.0025 (11)	0.0017 (12)
C5	0.0568 (15)	0.109 (2)	0.0482 (13)	−0.0211 (14)	0.0167 (12)	−0.0187 (15)
C6	0.0523 (15)	0.0930 (18)	0.0732 (17)	0.0105 (13)	0.0152 (13)	−0.0237 (15)
C7	0.0464 (12)	0.0656 (12)	0.0572 (13)	0.0076 (10)	0.0028 (11)	−0.0081 (11)
C8	0.0313 (9)	0.0397 (9)	0.0310 (9)	0.0004 (7)	0.0020 (7)	0.0017 (8)
C9	0.0339 (9)	0.0363 (8)	0.0352 (10)	−0.0007 (7)	0.0051 (8)	−0.0005 (8)
C10	0.0560 (12)	0.0483 (10)	0.0414 (11)	−0.0051 (10)	−0.0024 (9)	−0.0026 (9)
C11	0.0712 (15)	0.0511 (12)	0.0611 (15)	−0.0175 (10)	0.0012 (12)	−0.0137 (12)
C12	0.0751 (15)	0.0384 (10)	0.0633 (13)	−0.0080 (10)	0.0131 (12)	0.0023 (11)
C13	0.0594 (13)	0.0429 (10)	0.0529 (13)	0.0007 (9)	0.0052 (10)	0.0099 (10)
C14	0.0442 (11)	0.0415 (9)	0.0416 (10)	−0.0015 (8)	0.0012 (8)	0.0026 (9)
C15	0.0369 (10)	0.0333 (8)	0.0380 (10)	0.0033 (7)	−0.0080 (8)	0.0034 (8)
C16	0.0545 (12)	0.0409 (9)	0.0488 (12)	−0.0062 (8)	−0.0097 (10)	0.0058 (9)
C17	0.0739 (16)	0.0410 (10)	0.0798 (18)	−0.0098 (10)	−0.0277 (14)	0.0023 (12)
C18	0.0845 (18)	0.0490 (11)	0.0682 (17)	0.0092 (12)	−0.0348 (14)	−0.0176 (12)
C19	0.0716 (16)	0.0685 (15)	0.0465 (12)	0.0149 (13)	−0.0105 (11)	−0.0109 (12)
C20	0.0520 (12)	0.0501 (11)	0.0421 (11)	0.0020 (9)	−0.0028 (9)	−0.0037 (10)
C21	0.0317 (9)	0.0365 (8)	0.0410 (11)	−0.0018 (7)	−0.0039 (8)	−0.0017 (8)
C22	0.0417 (11)	0.0644 (11)	0.0574 (13)	0.0009 (10)	−0.0059 (10)	0.0180 (12)
C23	0.0558 (14)	0.0701 (13)	0.0771 (17)	0.0055 (11)	−0.0182 (13)	0.0245 (13)
C24	0.0489 (13)	0.0501 (11)	0.0866 (18)	0.0090 (9)	−0.0288 (13)	−0.0054 (13)
C25	0.0361 (11)	0.0703 (13)	0.0739 (16)	0.0085 (10)	−0.0039 (11)	−0.0200 (13)
C26	0.0400 (10)	0.0628 (12)	0.0508 (12)	0.0055 (9)	0.0001 (10)	−0.0017 (11)

Geometric parameters (Å, º) top

O1—C1	1.351 (2)	C13—C14	1.382 (3)
O1—C8	1.470 (2)	C13—H13	0.9300
O2—C1	1.200 (2)	C14—H14	0.9300
C1—C2	1.486 (2)	C15—C16	1.389 (3)
C2—C3	1.382 (3)	C15—C20	1.393 (3)
C2—C7	1.388 (3)	C16—C17	1.384 (3)
C3—C4	1.390 (3)	C16—H16	0.9300
C3—H3	0.9300	C17—C18	1.373 (4)
C4—C5	1.370 (4)	C17—H17	0.9300
C4—H4	0.9300	C18—C19	1.367 (3)
C5—C6	1.369 (4)	C18—H18	0.9300
C5—H5	0.9300	C19—C20	1.382 (3)
C6—C7	1.378 (3)	C19—H19	0.9300
C6—H6	0.9300	C20—H20	0.9300
C7—H7	0.9300	C21—C22	1.380 (3)
C8—C15	1.529 (2)	C21—C26	1.383 (3)
C8—C9	1.540 (2)	C22—C23	1.386 (3)
C8—C21	1.541 (2)	C22—H22	0.9300
C9—C10	1.388 (3)	C23—C24	1.362 (3)
C9—C14	1.392 (3)	C23—H23	0.9300
C10—C11	1.387 (3)	C24—C25	1.368 (3)
C10—H10	0.9300	C24—H24	0.9300
C11—C12	1.372 (3)	C25—C26	1.379 (3)
C11—H11	0.9300	C25—H25	0.9300
C12—C13	1.371 (3)	C26—H26	0.9300
C12—H12	0.9300

C1—O1—C8	120.50 (13)	C12—C13—H13	119.6
O2—C1—O1	124.44 (16)	C14—C13—H13	119.6
O2—C1—C2	124.32 (15)	C13—C14—C9	120.44 (19)
O1—C1—C2	111.22 (15)	C13—C14—H14	119.8
C3—C2—C7	119.40 (19)	C9—C14—H14	119.8
C3—C2—C1	122.47 (17)	C16—C15—C20	118.12 (17)
C7—C2—C1	118.09 (18)	C16—C15—C8	120.72 (17)
C2—C3—C4	120.5 (2)	C20—C15—C8	120.79 (16)
C2—C3—H3	119.8	C17—C16—C15	120.3 (2)
C4—C3—H3	119.8	C17—C16—H16	119.8
C5—C4—C3	119.4 (2)	C15—C16—H16	119.8
C5—C4—H4	120.3	C18—C17—C16	120.8 (2)
C3—C4—H4	120.3	C18—C17—H17	119.6
C6—C5—C4	120.4 (2)	C16—C17—H17	119.6
C6—C5—H5	119.8	C19—C18—C17	119.5 (2)
C4—C5—H5	119.8	C19—C18—H18	120.3
C5—C6—C7	120.8 (2)	C17—C18—H18	120.3
C5—C6—H6	119.6	C18—C19—C20	120.5 (2)
C7—C6—H6	119.6	C18—C19—H19	119.7
C6—C7—C2	119.5 (2)	C20—C19—H19	119.7
C6—C7—H7	120.2	C19—C20—C15	120.7 (2)
C2—C7—H7	120.2	C19—C20—H20	119.6
O1—C8—C15	110.20 (13)	C15—C20—H20	119.6
O1—C8—C9	108.33 (13)	C22—C21—C26	117.85 (18)
C15—C8—C9	116.08 (14)	C22—C21—C8	122.77 (16)
O1—C8—C21	103.39 (13)	C26—C21—C8	119.32 (16)
C15—C8—C21	107.19 (12)	C21—C22—C23	120.5 (2)
C9—C8—C21	110.90 (13)	C21—C22—H22	119.7
C10—C9—C14	118.24 (16)	C23—C22—H22	119.7
C10—C9—C8	119.00 (15)	C24—C23—C22	120.8 (2)
C14—C9—C8	122.71 (16)	C24—C23—H23	119.6
C11—C10—C9	120.7 (2)	C22—C23—H23	119.6
C11—C10—H10	119.7	C23—C24—C25	119.4 (2)
C9—C10—H10	119.7	C23—C24—H24	120.3
C12—C11—C10	120.3 (2)	C25—C24—H24	120.3
C12—C11—H11	119.8	C24—C25—C26	120.2 (2)
C10—C11—H11	119.8	C24—C25—H25	119.9
C13—C12—C11	119.56 (18)	C26—C25—H25	119.9
C13—C12—H12	120.2	C25—C26—C21	121.2 (2)
C11—C12—H12	120.2	C25—C26—H26	119.4
C12—C13—C14	120.7 (2)	C21—C26—H26	119.4

Experimental details

Crystal data
Chemical formula	C₂₆H₂₀O₂
M_r	364.42
Crystal system, space group	Orthorhombic, Pna2₁
Temperature (K)	290
a, b, c (Å)	8.9512 (4), 14.9545 (5), 14.4038 (6)
V (Å³)	1928.10 (13)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.50 × 0.15 × 0.07

Data collection
Diffractometer	Oxford Diffraction Xcalibur diffractometer with an Eos CCD detector
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.959, 0.995
No. of measured, independent and observed [I > 2σ(I)] reflections	6656, 2664, 1879
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.713

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.070, 0.91
No. of reflections	2664
No. of parameters	254
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.12, −0.12

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXP97 (Sheldrick, 2008), publCIF (Westrip, 2009).

Acknowledgements

The authors gratefully acknowledge the National Science Foundation for their generous support (NSF-CAREER grant to RES, CHE-0846680).

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