1,3-Bis(4-methyl­benzo­yl)-2,4-bis­(2,4,5-tri­meth­oxy­phen­yl)cyclo­butane

Raghavendra, K.R.; Naveen, S.; Renuka, N.; Prabhudeva, M.G.; Lokanath, N.K.; Ajay Kumar, K.

doi:10.1107/S2414314617001134

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 1| January 2017| x170113

https://doi.org/10.1107/S2414314617001134

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access

1,3-Bis(4-methylbenzoyl)-2,4-bis(2,4,5-trimethoxyphenyl)cyclobutane

K. R. Raghavendra,^a S. Naveen,^b ^* N. Renuka,^c M. G. Prabhudeva,^c N. K. Lokanath ^d and K. Ajay Kumar ^c ^*

^aDepartment of Chemistry, SBRR Mahajana College, Mysuru 570 006, India, ^bInstitution of Excellence, University of Mysore, Manasagangotri, Mysuru 570 006, India, ^cDepartment of Chemistry, Yuvaraja's College, University of Mysore, Mysuru 570 005, India, and ^dDepartment of Studies in Physics, University of Mysore, Manasagangotri, Mysuru 570 006, India
^*Correspondence e-mail: naveen@ioe.uni-mysore.ac.in, ajaykumar@ycm.uni-mysore.ac.in

Edited by D.-J. Xu, Zhejiang University (Yuquan Campus), China (Received 19 January 2017; accepted 23 January 2017; online 27 January 2017)

The title compound, C₃₈H₄₀O₈, possess an inversion centre at the centroid of the four-membered ring. The dihedral angle between the methylbenzene and trimethoxybenzene rings is 46.19 (8)°. In the crystal, molecules are linked via weak C—H⋯π interactions, forming centrosymmetric supramolecular dimers.

Keywords: crystal structure; bis-chalcone; cyclobutane.

CCDC reference: 1529177

Structure description

Recently, a new route to polysubstituted cyclobutanes via K₂S₂O₈-promoted [2 + 2]-cycloaddition was reported (Zhu et al., 2016 ). We carried out a reaction of 2,4,5-trimethoxybenzaldehyde and 4-methyl acetophenone in the presence of in 95% ethyl alcohol under reflux conditions. After completion, the reaction unexpectedly yielded the title compound via the intermolecular [2 + 2]-cycloaddition of the expected (E)-1-(p-tolyl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one.

The molecular structure of the title compound is shown in Fig. 1. The molecule is located about an inversion centre at the centroid of the four-membered ring. The dihedral angle between the aromatic rings is 46.19 (8)°. The methoxy groups at C4 and C6 lie close to the plane of theeir attached benzene ring, as indicated by the torsion angle values of −7.2 (2)° and 174.05 (14)° for C8—O3—C4—C5 and C7—O2—C6—C1 respectively whereas the methoxy group at C3 is twisted out of the plane of the benzene ring [C9—O4—C3—C2 = 119.22 (17)°] . In the crystal, the molecules are linked via weak C—H⋯π interactions (Table 1), forming centrosymmetric supramolecular dimers.

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7C⋯Cg2ⁱ	0.96	2.75	3.5764 (19)	145
Symmetry code: (i) -x, -y+1, -z+1.

Figure 1
The molecular structure of the title compound with the atom-numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level.

Synthesis and crystallization

A mixture of 2,4,5-trimethoxybenzaldehyde (5 mmol), 4-methyl acetophenone (5 mmol) and sodium hydroxide (5 mmol) in 95% ethyl alcohol (25 ml) was refluxed on a water bath conditions for 1 h. The progress of the reaction was monitored by TLC. After the completion of the reaction, the mixture was poured into ice-cold water and kept in the refrigerator overnight. The solid that formed was filtered, and washed with cold hydrochloric acid (5%). Recrystallization from methanol solution yielded yellow slabs of the title compound. Yield 78%, m.p. 108–110 °C.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₃₈H₄₀O₈
M_r	624.70
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	296
a, b, c (Å)	8.1155 (4), 9.9316 (5), 11.0656 (6)
α, β, γ (°)	70.471 (1), 81.955 (1), 67.854 (1)
V (Å³)	778.47 (7)
Z	1
Radiation type	Cu Kα
μ (mm⁻¹)	0.76
Crystal size (mm)	0.28 × 0.25 × 0.22

Data collection
Diffractometer	Bruker X8 Proteum
Absorption correction	Multi-scan (SADABS; Bruker, 2013 )
T_min, T_max	0.817, 0.852
No. of measured, independent and observed [I > 2σ(I)] reflections	8126, 2539, 2458
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.585

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.154, 1.05
No. of reflections	2539
No. of parameters	212
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.34, −0.25
Computer programs: APEX2 and SAINT (Bruker, 2013), SHELXS97 and SHELXL97 (Sheldrick, 2008 ), Mercury (Macrae et al., 2008 ) and PLATON (Spek, 2009 ).

Structural data

CCDC reference: 1529177

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314617001134/xu4021sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617001134/xu4021Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617001134/xu4021Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); 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 PLATON (Spek, 2009).

1,3-Bis(4-methylbenzoyl)-2,4-bis(2,4,5-trimethoxyphenyl)cyclobutane top

Crystal data top

C₃₈H₄₀O₈	Z = 1
M_r = 624.70	F(000) = 332
Triclinic, P1	D_x = 1.332 Mg m⁻³
Hall symbol: -P 1	Cu Kα radiation, λ = 1.54178 Å
a = 8.1155 (4) Å	Cell parameters from 2458 reflections
b = 9.9316 (5) Å	θ = 5.9–64.3°
c = 11.0656 (6) Å	µ = 0.76 mm⁻¹
α = 70.471 (1)°	T = 296 K
β = 81.955 (1)°	Rectangle, yellow
γ = 67.854 (1)°	0.28 × 0.25 × 0.22 mm
V = 778.47 (7) Å³

Data collection top

Bruker X8 Proteum diffractometer	2539 independent reflections
Radiation source: Bruker MicroStar microfocus rotating anode	2458 reflections with I > 2σ(I)
Helios multilayer optics monochromator	R_int = 0.042
Detector resolution: 18.4 pixels mm^-1	θ_max = 64.3°, θ_min = 5.9°
φ and ω scans	h = −8→9
Absorption correction: multi-scan (SADABS; Bruker, 2013)	k = −11→11
T_min = 0.817, T_max = 0.852	l = −12→12
8126 measured reflections

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) = 0.154	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.1056P)² + 0.2971P] where P = (F_o² + 2F_c²)/3
2539 reflections	(Δ/σ)_max < 0.001
212 parameters	Δρ_max = 0.34 e Å⁻³
0 restraints	Δρ_min = −0.25 e Å⁻³

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F² for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > 2sigma(F²) is used only for calculating -R-factor-obs 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	0.44259 (16)	0.19813 (15)	0.23209 (11)	0.0295 (4)
O2	0.01550 (14)	0.26130 (12)	0.51807 (11)	0.0198 (3)
O3	0.11060 (15)	0.46294 (13)	0.83588 (11)	0.0230 (3)
O4	0.47051 (15)	0.31512 (13)	0.81383 (11)	0.0223 (3)
C1	0.3046 (2)	0.20001 (17)	0.58511 (14)	0.0162 (4)
C2	0.4151 (2)	0.21892 (17)	0.65963 (15)	0.0175 (5)
C3	0.3506 (2)	0.30910 (17)	0.74005 (15)	0.0175 (5)
C4	0.1670 (2)	0.38172 (17)	0.75073 (15)	0.0179 (5)
C5	0.0533 (2)	0.36687 (17)	0.67677 (15)	0.0180 (5)
C6	0.1219 (2)	0.27751 (17)	0.59445 (14)	0.0162 (5)
C7	−0.1718 (2)	0.32646 (19)	0.53436 (16)	0.0220 (5)
C8	−0.0744 (2)	0.55118 (19)	0.83837 (17)	0.0248 (5)
C9	0.4770 (2)	0.4642 (2)	0.78940 (19)	0.0297 (6)
C10	0.3761 (2)	0.10060 (17)	0.49825 (15)	0.0164 (5)
C11	0.5654 (2)	0.07947 (17)	0.44097 (15)	0.0165 (5)
C12	0.5760 (2)	0.14150 (17)	0.29597 (15)	0.0184 (5)
C13	0.7536 (2)	0.13001 (17)	0.23417 (15)	0.0186 (5)
C14	0.9074 (2)	0.07966 (18)	0.30416 (15)	0.0199 (5)
C15	1.0701 (2)	0.06841 (18)	0.24225 (16)	0.0222 (5)
C16	1.0864 (2)	0.10438 (18)	0.10918 (16)	0.0215 (5)
C17	0.9319 (2)	0.15728 (18)	0.03947 (16)	0.0228 (5)
C18	0.7680 (2)	0.17084 (18)	0.10031 (16)	0.0208 (5)
C19	1.2655 (2)	0.0854 (2)	0.04421 (17)	0.0269 (5)
H2	0.53720	0.16870	0.65500	0.0210*
H5	−0.06890	0.41670	0.68220	0.0220*
H7A	−0.20530	0.28090	0.62070	0.0330*
H7B	−0.23080	0.30790	0.47550	0.0330*
H7C	−0.20570	0.43450	0.51790	0.0330*
H8A	−0.11030	0.62020	0.75420	0.0370*
H8B	−0.09580	0.60840	0.89740	0.0370*
H8C	−0.14150	0.48430	0.86520	0.0370*
H9A	0.50480	0.50400	0.70040	0.0450*
H9B	0.56710	0.45760	0.84120	0.0450*
H9C	0.36360	0.53080	0.81030	0.0450*
H10	0.29200	0.13580	0.42910	0.0200*
H11	0.62770	0.12040	0.48140	0.0200*
H14	0.90040	0.05350	0.39320	0.0240*
H15	1.17070	0.03610	0.29040	0.0270*
H17	0.93920	0.18390	−0.04950	0.0270*
H18	0.66660	0.20740	0.05180	0.0250*
H19A	1.30410	0.16480	0.04640	0.0400*
H19B	1.25710	0.09150	−0.04330	0.0400*
H19C	1.34970	−0.01230	0.08800	0.0400*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0193 (6)	0.0386 (8)	0.0237 (7)	−0.0057 (5)	−0.0007 (5)	−0.0061 (5)
O2	0.0152 (6)	0.0226 (6)	0.0242 (6)	−0.0059 (5)	−0.0006 (4)	−0.0114 (5)
O3	0.0209 (6)	0.0233 (6)	0.0253 (6)	−0.0018 (5)	−0.0009 (5)	−0.0149 (5)
O4	0.0221 (6)	0.0211 (6)	0.0260 (6)	−0.0057 (5)	−0.0059 (5)	−0.0101 (5)
C1	0.0171 (8)	0.0130 (7)	0.0174 (8)	−0.0050 (6)	0.0013 (6)	−0.0044 (6)
C2	0.0148 (8)	0.0156 (8)	0.0203 (8)	−0.0042 (6)	0.0006 (6)	−0.0050 (6)
C3	0.0183 (8)	0.0150 (8)	0.0187 (8)	−0.0058 (6)	−0.0024 (6)	−0.0039 (6)
C4	0.0212 (8)	0.0149 (8)	0.0166 (8)	−0.0048 (6)	0.0018 (6)	−0.0063 (6)
C5	0.0152 (8)	0.0154 (8)	0.0210 (8)	−0.0037 (6)	0.0022 (6)	−0.0054 (6)
C6	0.0168 (8)	0.0149 (8)	0.0171 (8)	−0.0070 (6)	0.0002 (6)	−0.0038 (6)
C7	0.0160 (8)	0.0233 (9)	0.0282 (9)	−0.0074 (7)	−0.0006 (6)	−0.0091 (7)
C8	0.0212 (9)	0.0236 (9)	0.0293 (9)	−0.0026 (7)	0.0020 (7)	−0.0148 (7)
C9	0.0263 (9)	0.0270 (10)	0.0428 (11)	−0.0105 (8)	−0.0044 (8)	−0.0166 (8)
C10	0.0147 (8)	0.0157 (8)	0.0186 (8)	−0.0041 (6)	−0.0002 (6)	−0.0065 (6)
C11	0.0149 (8)	0.0158 (8)	0.0212 (8)	−0.0053 (6)	0.0013 (6)	−0.0093 (6)
C12	0.0202 (9)	0.0132 (7)	0.0223 (8)	−0.0048 (6)	−0.0008 (7)	−0.0070 (6)
C13	0.0215 (9)	0.0135 (8)	0.0218 (8)	−0.0068 (6)	0.0031 (7)	−0.0073 (6)
C14	0.0239 (9)	0.0175 (8)	0.0175 (8)	−0.0079 (7)	0.0015 (6)	−0.0045 (6)
C15	0.0208 (8)	0.0194 (8)	0.0259 (9)	−0.0071 (7)	−0.0014 (7)	−0.0061 (7)
C16	0.0240 (9)	0.0145 (8)	0.0264 (9)	−0.0081 (6)	0.0039 (7)	−0.0072 (6)
C17	0.0289 (9)	0.0204 (8)	0.0180 (8)	−0.0096 (7)	0.0039 (7)	−0.0051 (6)
C18	0.0223 (9)	0.0183 (8)	0.0212 (8)	−0.0062 (7)	−0.0014 (6)	−0.0060 (6)
C19	0.0269 (9)	0.0259 (9)	0.0271 (9)	−0.0110 (7)	0.0058 (7)	−0.0076 (7)

Geometric parameters (Å, º) top

O1—C12	1.216 (2)	C16—C19	1.502 (3)
O2—C6	1.373 (2)	C17—C18	1.384 (2)
O2—C7	1.422 (2)	C2—H2	0.9300
O3—C4	1.363 (2)	C5—H5	0.9300
O3—C8	1.427 (2)	C7—H7A	0.9600
O4—C3	1.384 (2)	C7—H7B	0.9600
O4—C9	1.434 (2)	C7—H7C	0.9600
C1—C2	1.399 (2)	C8—H8A	0.9600
C1—C6	1.397 (2)	C8—H8B	0.9600
C1—C10	1.511 (2)	C8—H8C	0.9600
C2—C3	1.385 (2)	C9—H9A	0.9600
C3—C4	1.397 (2)	C9—H9B	0.9600
C4—C5	1.392 (2)	C9—H9C	0.9600
C5—C6	1.398 (2)	C10—H10	0.9800
C10—C11	1.543 (2)	C11—H11	0.9800
C10—C11ⁱ	1.588 (2)	C14—H14	0.9300
C11—C12	1.517 (2)	C15—H15	0.9300
C12—C13	1.487 (2)	C17—H17	0.9300
C13—C14	1.396 (2)	C18—H18	0.9300
C13—C18	1.399 (2)	C19—H19A	0.9600
C14—C15	1.383 (2)	C19—H19B	0.9600
C15—C16	1.394 (2)	C19—H19C	0.9600
C16—C17	1.395 (2)

C6—O2—C7	117.55 (13)	C6—C5—H5	120.00
C4—O3—C8	117.44 (14)	O2—C7—H7A	109.00
C3—O4—C9	114.77 (13)	O2—C7—H7B	109.00
C2—C1—C6	116.90 (14)	O2—C7—H7C	109.00
C2—C1—C10	122.54 (15)	H7A—C7—H7B	109.00
C6—C1—C10	120.56 (15)	H7A—C7—H7C	109.00
C1—C2—C3	122.91 (16)	H7B—C7—H7C	109.00
O4—C3—C2	118.38 (15)	O3—C8—H8A	109.00
O4—C3—C4	122.34 (14)	O3—C8—H8B	109.00
C2—C3—C4	119.12 (16)	O3—C8—H8C	109.00
O3—C4—C3	116.61 (15)	H8A—C8—H8B	109.00
O3—C4—C5	123.95 (15)	H8A—C8—H8C	109.00
C3—C4—C5	119.45 (15)	H8B—C8—H8C	110.00
C4—C5—C6	120.32 (16)	O4—C9—H9A	109.00
O2—C6—C1	116.25 (14)	O4—C9—H9B	109.00
O2—C6—C5	122.50 (15)	O4—C9—H9C	109.00
C1—C6—C5	121.26 (15)	H9A—C9—H9B	109.00
C1—C10—C11	118.41 (14)	H9A—C9—H9C	110.00
C1—C10—C11ⁱ	119.20 (13)	H9B—C9—H9C	109.00
C11—C10—C11ⁱ	89.08 (12)	C1—C10—H10	110.00
C10—C11—C12	115.28 (14)	C11—C10—H10	110.00
C10—C11—C10ⁱ	90.92 (12)	C11ⁱ—C10—H10	110.00
C10ⁱ—C11—C12	116.86 (13)	C10—C11—H11	111.00
O1—C12—C11	120.71 (15)	C12—C11—H11	111.00
O1—C12—C13	120.96 (14)	C10ⁱ—C11—H11	111.00
C11—C12—C13	118.33 (14)	C13—C14—H14	120.00
C12—C13—C14	122.74 (14)	C15—C14—H14	120.00
C12—C13—C18	118.87 (15)	C14—C15—H15	119.00
C14—C13—C18	118.39 (16)	C16—C15—H15	119.00
C13—C14—C15	120.54 (15)	C16—C17—H17	119.00
C14—C15—C16	121.40 (16)	C18—C17—H17	119.00
C15—C16—C17	117.85 (16)	C13—C18—H18	120.00
C15—C16—C19	120.54 (16)	C17—C18—H18	120.00
C17—C16—C19	121.61 (15)	C16—C19—H19A	110.00
C16—C17—C18	121.23 (16)	C16—C19—H19B	109.00
C13—C18—C17	120.54 (16)	C16—C19—H19C	109.00
C1—C2—H2	119.00	H19A—C19—H19B	109.00
C3—C2—H2	119.00	H19A—C19—H19C	109.00
C4—C5—H5	120.00	H19B—C19—H19C	109.00

C7—O2—C6—C1	174.05 (14)	C1—C10—C11—C12	−116.41 (16)
C7—O2—C6—C5	−6.3 (2)	C1—C10—C11—C10ⁱ	123.10 (14)
C8—O3—C4—C3	173.45 (14)	C11ⁱ—C10—C11—C12	120.49 (14)
C8—O3—C4—C5	−7.2 (2)	C11ⁱ—C10—C11—C10ⁱ	0.00 (11)
C9—O4—C3—C2	119.22 (17)	C1—C10—C11ⁱ—C10ⁱ	−122.43 (16)
C9—O4—C3—C4	−65.4 (2)	C1—C10—C11ⁱ—C12ⁱ	−3.3 (2)
C6—C1—C2—C3	0.2 (2)	C11—C10—C11ⁱ—C10ⁱ	0.00 (10)
C10—C1—C2—C3	−179.61 (15)	C11—C10—C11ⁱ—C12ⁱ	119.13 (15)
C2—C1—C6—O2	178.24 (14)	C10—C11—C12—O1	−2.6 (2)
C2—C1—C6—C5	−1.4 (2)	C10—C11—C12—C13	177.95 (14)
C10—C1—C6—O2	−2.0 (2)	C10ⁱ—C11—C12—O1	102.45 (19)
C10—C1—C6—C5	178.38 (15)	C10ⁱ—C11—C12—C13	−77.0 (2)
C2—C1—C10—C11	−28.5 (2)	O1—C12—C13—C14	173.58 (17)
C2—C1—C10—C11ⁱ	77.8 (2)	O1—C12—C13—C18	−6.6 (2)
C6—C1—C10—C11	151.72 (15)	C11—C12—C13—C14	−6.9 (2)
C6—C1—C10—C11ⁱ	−101.93 (18)	C11—C12—C13—C18	172.89 (15)
C1—C2—C3—O4	177.31 (15)	C12—C13—C14—C15	178.84 (16)
C1—C2—C3—C4	1.8 (2)	C18—C13—C14—C15	−1.0 (3)
O4—C3—C4—O3	1.6 (2)	C12—C13—C18—C17	−178.03 (16)
O4—C3—C4—C5	−177.83 (15)	C14—C13—C18—C17	1.8 (3)
C2—C3—C4—O3	176.91 (14)	C13—C14—C15—C16	−1.0 (3)
C2—C3—C4—C5	−2.5 (2)	C14—C15—C16—C17	2.1 (3)
O3—C4—C5—C6	−178.04 (15)	C14—C15—C16—C19	−177.55 (17)
C3—C4—C5—C6	1.3 (2)	C15—C16—C17—C18	−1.3 (3)
C4—C5—C6—O2	−178.93 (14)	C19—C16—C17—C18	178.38 (17)
C4—C5—C6—C1	0.7 (2)	C16—C17—C18—C13	−0.7 (3)

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7C···Cg2ⁱⁱ	0.96	2.75	3.5764 (19)	145

Symmetry code: (ii) −x, −y+1, −z+1.

Acknowledgements

The authors are grateful to the Institution of Excellence, Vijnana Bhavana, University of Mysore, India, for providing the single-crystal X-ray diffractometer facility.

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