Cocrystals of 1,4-diethynyl­benzene with 1,3-di­acetyl­benzene and benzene-1,4-dicarbaldehyde exhibiting strong nonconventional alkyne–carbonyl C—H...O hydrogen bonds between the components

Weak inter­actions between organic mol­ecules are important in solid-state structures where the sum of the weaker inter­actions support the overall three-dimensional crystal structure. The sp-C—H...N hydrogen-bonding inter­action is strong enough to promote the deliberate cocrystallization of a series of diynes with a series of di­pyridines. It is also possible that a similar series of cocrystals could be formed between molecules containing a terminal alkyne and molecules which contain carbonyl O atoms as the potential hydrogen-bond acceptor. I now report the crystal structure of two cocrystals that support this hypothesis. The 1:1 cocrystal of 1,4-diethynyl­benzene with 1,3-di­acetyl­benzene, C₁₀H₆·C₁₀H₁₀O₂, (1), and the 1:1 cocrystal of 1,4-diethynyl­benzene with benzene-1,4-dicarbaldehyde, C₁₀H₆·C₈H₆O₂, (2), are presented. In both cocrystals, a strong nonconventional ethyn­yl–carbonyl sp-C—H...O hydrogen bond is observed between the components. In cocrystal (1), the C—H...O hydrogen-bond angle is 171.8 (16)° and the H...O and C...O hydrogen-bond distances are 2.200 (19) and 3.139 (2) Å, respectively. In cocrystal (2), the C—H...O hydrogen-bond angle is 172.5 (16)° and the H...O and C...O hydrogen-bond distances are 2.25 (2) and 3.203 (2) Å, respectively.

Computing details

For both compounds, data collection: SMART (Bruker, 2012); cell refinement: SMART (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: X-SEED (Barbour, 2001).

(1) 1-(3-Acetylphenyl)ethan-1-one–1,4-diethynylbenzene (1/1)

Crystal data

C10H6·C10H10O2	F(000) = 608
Mr = 288.33	Dx = 1.229 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 19.749 (10) Å	Cell parameters from 2546 reflections
b = 7.284 (3) Å	θ = 2.6–27.0°
c = 13.374 (7) Å	µ = 0.08 mm^−1
β = 125.890 (13)°	T = 173 K
V = 1558.6 (13) Å^3	Irregular, yellow
Z = 4	0.43 × 0.33 × 0.32 mm

Data collection

Bruker APEXII CCD diffractometer	1741 independent reflections
Radiation source: fine-focus sealed tube	1356 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.079
Detector resolution: 8.3660 pixels mm^-1	θmax = 27.2°, θmin = 2.6°
phi and ω scans	h = −25→25
Absorption correction: multi-scan (SADABS; Bruker, 2012)	k = −9→9
Tmin = 0.492, Tmax = 0.746	l = −17→17
9573 measured reflections

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F^2 > 2σ(F^2)] = 0.051	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.159	w = 1/[σ^2(Fo^2) + (0.1007P)^2 + 0.1951P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max < 0.001
1741 reflections	Δρmax = 0.28 e Å^−3
106 parameters	Δρmin = −0.30 e Å^−3

Special details

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.39785 (6)	0.49943 (17)	0.42438 (9)	0.0420 (4)
C1	0.5000	0.7982 (3)	0.7500	0.0418 (5)
H1	0.5000	0.9286	0.7500	0.050*
C2	0.46566 (9)	0.7038 (2)	0.64051 (14)	0.0367 (4)
H2	0.4423	0.7697	0.5657	0.044*
C3	0.46517 (8)	0.5125 (2)	0.63941 (12)	0.0292 (4)
C4	0.5000	0.4185 (3)	0.7500	0.0290 (5)
H4	0.5000	0.2881	0.7500	0.035*
C5	0.42691 (9)	0.4141 (2)	0.51946 (13)	0.0314 (4)
C6	0.42518 (11)	0.2082 (2)	0.51840 (14)	0.0445 (4)
H6A	0.3975	0.1640	0.4337	0.067*
H6B	0.3944	0.1650	0.5506	0.067*
H6C	0.4825	0.1611	0.5703	0.067*
C7	0.25624 (9)	1.4300 (2)	0.03752 (13)	0.0351 (4)
H7	0.2606	1.5537	0.0632	0.042*
C8	0.28409 (9)	1.2900 (2)	0.12288 (13)	0.0343 (4)
H8	0.3072	1.3177	0.2066	0.041*
C9	0.27822 (9)	1.1082 (2)	0.08614 (13)	0.0326 (4)
C10	0.30741 (10)	0.9613 (2)	0.17345 (14)	0.0380 (4)
C11	0.33131 (11)	0.8371 (3)	0.24456 (16)	0.0472 (5)
H11	0.3485 (11)	0.740 (3)	0.3019 (16)	0.059 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0521 (7)	0.0392 (7)	0.0296 (6)	0.0050 (5)	0.0211 (5)	0.0075 (4)
C1	0.0543 (13)	0.0211 (10)	0.0487 (13)	0.000	0.0295 (11)	0.000
C2	0.0454 (9)	0.0262 (8)	0.0387 (9)	0.0034 (6)	0.0249 (7)	0.0059 (6)
C3	0.0335 (7)	0.0239 (7)	0.0307 (8)	0.0007 (5)	0.0191 (6)	0.0018 (5)
C4	0.0356 (10)	0.0215 (10)	0.0299 (10)	0.000	0.0192 (8)	0.000
C5	0.0343 (7)	0.0305 (8)	0.0275 (7)	0.0004 (5)	0.0171 (6)	0.0019 (5)
C6	0.0630 (10)	0.0305 (8)	0.0310 (8)	−0.0074 (7)	0.0226 (8)	−0.0044 (6)
C7	0.0419 (8)	0.0249 (7)	0.0349 (8)	0.0028 (6)	0.0204 (7)	0.0014 (6)
C8	0.0404 (8)	0.0306 (8)	0.0291 (7)	0.0019 (6)	0.0187 (6)	0.0006 (5)
C9	0.0330 (7)	0.0304 (8)	0.0313 (7)	0.0028 (6)	0.0171 (6)	0.0047 (6)
C10	0.0422 (8)	0.0326 (8)	0.0358 (8)	0.0020 (6)	0.0210 (7)	0.0029 (6)
C11	0.0562 (10)	0.0390 (9)	0.0386 (9)	0.0040 (7)	0.0234 (8)	0.0097 (7)

Geometric parameters (Å, º)

O1—C5	1.2154 (17)	C5—C6	1.500 (2)
C1—C2	1.383 (2)	C7—C8	1.382 (2)
C1—C2^i	1.383 (2)	C7—C9^ii	1.398 (2)
C2—C3	1.394 (2)	C8—C9	1.394 (2)
C3—C4	1.3915 (17)	C9—C7^ii	1.398 (2)
C3—C5	1.496 (2)	C9—C10	1.432 (2)
C4—C3^i	1.3915 (17)	C10—C11	1.192 (2)
C2—C1—C2^i	120.4 (2)	C3—C5—C6	118.92 (12)
C1—C2—C3	120.29 (15)	C8—C7—C9^ii	120.83 (14)
C4—C3—C2	118.99 (14)	C7—C8—C9	119.97 (14)
C4—C3—C5	121.89 (14)	C8—C9—C7^ii	119.20 (13)
C2—C3—C5	119.12 (13)	C8—C9—C10	120.80 (14)
C3^i—C4—C3	121.06 (19)	C7^ii—C9—C10	120.00 (14)
O1—C5—C3	120.58 (14)	C11—C10—C9	178.91 (17)
O1—C5—C6	120.49 (13)
C2^i—C1—C2—C3	0.14 (9)	C2—C3—C5—O1	1.2 (2)
C1—C2—C3—C4	−0.27 (19)	C4—C3—C5—C6	0.77 (18)
C1—C2—C3—C5	179.45 (10)	C2—C3—C5—C6	−178.94 (14)
C2—C3—C4—C3^i	0.14 (9)	C9^ii—C7—C8—C9	0.2 (2)
C5—C3—C4—C3^i	−179.58 (13)	C7—C8—C9—C7^ii	−0.2 (2)
C4—C3—C5—O1	−179.06 (11)	C7—C8—C9—C10	179.46 (13)

Symmetry codes: (i) −x+1, y, −z+3/2; (ii) −x+1/2, −y+5/2, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C11—H11···O1	0.946 (19)	2.200 (19)	3.139 (2)	171.8 (16)
C8—H8···O1^iii	0.95	2.71	3.607 (3)	158

Symmetry code: (iii) x, y+1, z.

(2) Benzene-1,4-dicarbaldehyde–1,4-diethynylbenzene (1/1)

Crystal data

C10H6·C8H6O2	F(000) = 272
Mr = 260.28	Dx = 1.289 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.6207 (11) Å	Cell parameters from 1102 reflections
b = 8.5205 (13) Å	θ = 3.1–24.9°
c = 10.3361 (15) Å	µ = 0.08 mm^−1
β = 91.762 (3)°	T = 100 K
V = 670.83 (17) Å^3	Cut block, gold
Z = 2	0.30 × 0.30 × 0.30 mm

Data collection

Bruker APEXII CCD diffractometer	1490 independent reflections
Radiation source: fine-focus sealed tube	1093 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.049
Detector resolution: 8.3660 pixels mm^-1	θmax = 27.2°, θmin = 2.7°
phi and ω scans	h = −9→9
Absorption correction: multi-scan (SADABS; Bruker, 2012)	k = −10→10
Tmin = 0.657, Tmax = 0.746	l = −13→13
8561 measured reflections

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F^2 > 2σ(F^2)] = 0.047	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.129	w = 1/[σ^2(Fo^2) + (0.0533P)^2 + 0.2043P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max < 0.001
1490 reflections	Δρmax = 0.32 e Å^−3
95 parameters	Δρmin = −0.20 e Å^−3

Special details

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.69613 (16)	0.50487 (14)	0.33121 (11)	0.0334 (3)
C1	0.8014 (2)	0.49771 (18)	0.63352 (16)	0.0271 (4)
H1	0.760 (2)	0.496 (2)	0.545 (2)	0.044 (6)*
C2	0.85696 (19)	0.49781 (17)	0.74283 (14)	0.0225 (4)
C3	0.92830 (18)	0.49889 (17)	0.87346 (14)	0.0207 (4)
C4	0.95879 (19)	0.35766 (18)	0.94029 (14)	0.0228 (4)
H4	0.9306	0.2606	0.8996	0.027*
C5	1.02972 (19)	0.35893 (18)	1.06519 (14)	0.0227 (4)
H5	1.0500	0.2627	1.1096	0.027*
C6	0.4196 (2)	0.38565 (18)	−0.07825 (15)	0.0241 (4)
H6	0.3643	0.3084	−0.1317	0.029*
C7	0.49060 (19)	0.34502 (19)	0.04163 (15)	0.0245 (4)
H7	0.4851	0.2394	0.0706	0.029*
C8	0.57054 (18)	0.45918 (19)	0.12032 (14)	0.0220 (4)
C9	0.6419 (2)	0.4130 (2)	0.24911 (14)	0.0272 (4)
H9	0.6457	0.3043	0.2693	0.033*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0375 (7)	0.0406 (8)	0.0216 (6)	0.0040 (5)	−0.0072 (5)	−0.0030 (5)
C1	0.0314 (9)	0.0262 (9)	0.0231 (9)	0.0011 (7)	−0.0047 (7)	−0.0011 (7)
C2	0.0242 (8)	0.0203 (8)	0.0228 (8)	0.0001 (6)	−0.0013 (6)	−0.0014 (6)
C3	0.0177 (7)	0.0263 (8)	0.0183 (8)	−0.0004 (6)	0.0002 (6)	−0.0007 (6)
C4	0.0247 (8)	0.0222 (8)	0.0214 (8)	−0.0010 (6)	−0.0023 (6)	−0.0033 (6)
C5	0.0245 (8)	0.0223 (8)	0.0212 (8)	0.0000 (6)	−0.0017 (6)	0.0015 (6)
C6	0.0237 (8)	0.0259 (8)	0.0227 (8)	−0.0011 (6)	−0.0007 (6)	−0.0035 (6)
C7	0.0261 (8)	0.0233 (8)	0.0242 (8)	0.0000 (6)	0.0005 (6)	0.0020 (6)
C8	0.0183 (7)	0.0285 (9)	0.0192 (8)	0.0020 (6)	0.0012 (6)	0.0006 (6)
C9	0.0270 (8)	0.0327 (10)	0.0217 (9)	0.0028 (7)	−0.0008 (7)	0.0017 (7)

Geometric parameters (Å, º)

O1—C9	1.2173 (19)	C5—C3^i	1.400 (2)
C1—C2	1.194 (2)	C6—C7	1.381 (2)
C2—C3	1.440 (2)	C6—C8^ii	1.395 (2)
C3—C5^i	1.400 (2)	C7—C8	1.396 (2)
C3—C4	1.403 (2)	C8—C6^ii	1.395 (2)
C4—C5	1.384 (2)	C8—C9	1.476 (2)
C1—C2—C3	178.54 (16)	C7—C6—C8^ii	119.60 (14)
C5^i—C3—C4	119.14 (14)	C6—C7—C8	120.01 (15)
C5^i—C3—C2	120.31 (13)	C6^ii—C8—C7	120.38 (14)
C4—C3—C2	120.54 (13)	C6^ii—C8—C9	120.80 (14)
C5—C4—C3	120.42 (14)	C7—C8—C9	118.81 (15)
C4—C5—C3^i	120.43 (14)	O1—C9—C8	124.42 (16)
C5^i—C3—C4—C5	−0.1 (2)	C6—C7—C8—C6^ii	−0.5 (2)
C2—C3—C4—C5	179.07 (13)	C6—C7—C8—C9	178.68 (14)
C3—C4—C5—C3^i	0.1 (2)	C6^ii—C8—C9—O1	7.8 (2)
C8^ii—C6—C7—C8	0.5 (2)	C7—C8—C9—O1	−171.33 (15)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1···O1	0.96 (2)	2.25 (2)	3.203 (2)	172.5 (16)
C7—H7···O1^iii	0.95	2.65	3.502 (2)	150

Symmetry code: (iii) −x+1, y−1/2, −z+1/2.