2,6-Diacetyl­pyridine–resorcinol (1/1)

Ton, Q.-C.; Bolte, M.

doi:10.1107/S1600536812035131

organic compounds

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Volume 68| Part 9| September 2012| Page o2699

doi:10.1107/S1600536812035131

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2,6-Diacetylpyridine–resorcinol (1/1)

Quoc-Cuong Ton ^a and Michael Bolte ^b ^*

^aInstitut für Organische Chemie und Chemische Biologie, Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany, and ^bInstitut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
^*Correspondence e-mail: bolte@chemie.uni-frankfurt.de

(Received 7 August 2012; accepted 8 August 2012; online 11 August 2012)

The title co-crystal, C₉H₉NO₂·C₆H₆O₂, is composed of one 2,6-diacetylpyridine molecule and one resorcinol molecule as the asymmetric unit. In the 2,6-diacetylpyridine molecule, the two carbonyl groups are antiperiplanar to the pyridine N atom. In the crystal, the 2,6-diacetylpyridine and resorcinol molecules are connected by two O—H⋯O hydrogen bonds, forming planar chains of alternating components running along [120].

Related literature

For background to 2,6-diacetylpyridine and resorcinol, see: Bacon & Lisher (1980 ); MacGillivray et al. (2000 ); Boldog et al. (2004 ); Matsumoto et al. (2006 ); Anwar et al. (2007 ); Friščić & MacGillivray (2009 ).

Experimental

Crystal data

C₉H₉NO₂·C₆H₆O₂
M_r = 273.28
Triclinic, $[P \overline 1]$
a = 7.346 (2) Å
b = 7.866 (2) Å
c = 12.342 (3) Å
α = 101.61 (3)°
β = 90.51 (3)°
γ = 98.72 (3)°
V = 689.9 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 173 K
0.30 × 0.30 × 0.23 mm

Data collection

Stoe IPDS II two-circle diffractometer
9113 measured reflections
2515 independent reflections
1605 reflections with I > 2σ(I)
R_int = 0.094

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.130
S = 0.93
2515 reflections
185 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—HO3⋯O2	0.84	1.95	2.784 (2)	174
O4—HO4⋯O1ⁱ	0.84	1.96	2.802 (3)	177
Symmetry code: (i) x+1, y+2, z.

Data collection: X-AREA (Stoe & Cie, 2001 ); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812035131/ng5287sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812035131/ng5287Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812035131/ng5287Isup3.cml

checkCIF report

Comment top

The co-crystallization process between two components which possess either donor or acceptor hydrogen bond properties in order to obtain the AAA-DDD (A=Acceptor, D= Donor) hydrogen bond pattern containing two strong O—H···O hydrogen bonds and one weak C—H···O hydrogen bond (see Fig. 1, III) was the initial motivation of this research. Therefore, 2,6-diacetylpyridine, I, (CSD REFCODE: BARKAH) and resorcinol, II, (CSD REFCODE: RESORA03) have been chosen for this purpose. Compounds I and II can exist in three possible conformations (Anwar et al., 2007). Considering all possible hydrogen bonds between the two components, forming the complex as mentioned above is the most unfavourable constellation. The calculations of the three molecular conformations of 2,6-diacetylpyridine using quantum-mechanical calculations (Gaussian 03) predict that conformer Ia is the most stable, followed by Ib, and then Ic. The determination of the relative stability of resorcinol using quantum–mechanical density functional theory (DFT) said that conformer IIa is the most stable, followed by IIb, and then IIc. Two out of three conformers of resorcinol have been observed in neutron powder experiments (Bacon & Lisher, 1980). Beyond that all three conformations have been found in diverse multi-component-complexes (Boldog et al. 2004; MacGillivray et al. 2000; Friščić & MacGillivray, 2009; Matsumoto et al., 2006) where resorcinol showed these conformations. Another possibility of building a finite hydrogen bond network between the two components is highlighted as an example (V in Fig. 1), where different conformers are involved. The energy for the conversion of the relative stable conformers Ia and IIb to the least energetically favoured conformational states Ic and IIc is estimated to be approximately 60 kJ/mol. The co-crystal of the title compound (Fig. 2) in the constellation of Ia and IIb adopts a chain motif (IV in Fig. 1) (Fig. 3). The desired complex (III in Fig. 1) was not formed.

Related literature top

For background to 2,6-diacetylpyridine and resorcinol, see: Bacon & Lisher (1980); MacGillivray et al. (2000); Boldog et al. (2004); Matsumoto et al. (2006); Anwar et al. (2007); Friščić & MacGillivray (2009).

Experimental top

The starting compounds 2,6-diacetylpyridine and resorcinol were purchased from Aldrich and Alfa Aesar which were used for co-crystallization experiments without purification. The starting compounds were dissolved in a 1:1 molecular ratio in ether and setlaid aside at room temperature. After several weeks adequate single crystals were obtained.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-RED32 (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. Scheme showing 2,6-diacetylpyridine (I) and resorcinol (II), their possible conformations (Ia, Ib, Ic, IIa, IIb, IIc) and hydrogen bonded complexes of them (III, IV, V).
	Fig. 2. A perspective view of the title complex, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 3. A partial packing diagram of the title complex. Dashed line indicate hydrogen bonds. Only the H atoms involved in hydrogen bonding are shown. [Symmetry codes: (i) -x + 1, -y + 2, -z + 1; (ii) -x, -y, -z + 1.]

1-(6-Acetylpyridin-2-yl)ethanone–benzene-1,3-diol (1/1) top

Crystal data top

C₉H₉NO₂·C₆H₆O₂	Z = 2
M_r = 273.28	F(000) = 288
Triclinic, P1	D_x = 1.315 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.346 (2) Å	Cell parameters from 9113 reflections
b = 7.866 (2) Å	θ = 3.8–25.6°
c = 12.342 (3) Å	µ = 0.10 mm⁻¹
α = 101.61 (3)°	T = 173 K
β = 90.51 (3)°	Block, colourless
γ = 98.72 (3)°	0.30 × 0.30 × 0.23 mm
V = 689.9 (3) Å³

Data collection top

Stoe IPDS II two-circle diffractometer	1605 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.094
Graphite monochromator	θ_max = 25.4°, θ_min = 3.2°
ω scans	h = −8→8
9113 measured reflections	k = −9→9
2515 independent reflections	l = −14→14

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) = 0.130	H-atom parameters constrained
S = 0.93	w = 1/[σ²(F_o²) + (0.0671P)²] where P = (F_o² + 2F_c²)/3
2515 reflections	(Δ/σ)_max < 0.001
185 parameters	Δρ_max = 0.19 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₉H₉NO₂·C₆H₆O₂	γ = 98.72 (3)°
M_r = 273.28	V = 689.9 (3) Å³
Triclinic, P1	Z = 2
a = 7.346 (2) Å	Mo Kα radiation
b = 7.866 (2) Å	µ = 0.10 mm⁻¹
c = 12.342 (3) Å	T = 173 K
α = 101.61 (3)°	0.30 × 0.30 × 0.23 mm
β = 90.51 (3)°

Data collection top

Stoe IPDS II two-circle diffractometer	1605 reflections with I > 2σ(I)
9113 measured reflections	R_int = 0.094
2515 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	0 restraints
wR(F²) = 0.130	H-atom parameters constrained
S = 0.93	Δρ_max = 0.19 e Å⁻³
2515 reflections	Δρ_min = −0.27 e Å⁻³
185 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 > 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
N1	0.2051 (2)	0.1792 (2)	0.23716 (14)	0.0241 (4)
O1	0.0057 (2)	−0.2404 (2)	0.27810 (15)	0.0442 (5)
O2	0.4266 (2)	0.6213 (2)	0.27795 (14)	0.0421 (5)
C1	0.2841 (2)	0.3381 (3)	0.29483 (18)	0.0244 (5)
C2	0.3093 (3)	0.3761 (3)	0.40993 (19)	0.0290 (5)
H2	0.3624	0.4906	0.4478	0.035*
C3	0.2559 (3)	0.2451 (3)	0.46820 (19)	0.0323 (5)
H3	0.2723	0.2674	0.5465	0.039*
C4	0.1779 (3)	0.0805 (3)	0.40953 (19)	0.0304 (5)
H4	0.1426	−0.0131	0.4469	0.036*
C5	0.1518 (2)	0.0537 (3)	0.29475 (18)	0.0243 (5)
C6	0.0608 (3)	−0.1218 (3)	0.22941 (19)	0.0283 (5)
C7	0.0371 (3)	−0.1447 (3)	0.1066 (2)	0.0385 (6)
H7A	0.0046	−0.2700	0.0734	0.058*
H7B	0.1526	−0.0971	0.0767	0.058*
H7C	−0.0614	−0.0821	0.0892	0.058*
C8	0.3460 (3)	0.4780 (3)	0.22922 (19)	0.0277 (5)
C9	0.3053 (3)	0.4348 (3)	0.1071 (2)	0.0371 (6)
H9A	0.3542	0.5361	0.0752	0.056*
H9B	0.1717	0.4063	0.0924	0.056*
H9C	0.3634	0.3336	0.0735	0.056*
O3	0.5190 (2)	0.8749 (2)	0.15119 (15)	0.0440 (5)
HO3	0.4909	0.8049	0.1937	0.066*
O4	0.8147 (2)	1.4495 (2)	0.14755 (14)	0.0437 (5)
HO4	0.8697	1.5413	0.1891	0.066*
C11	0.6121 (3)	1.0305 (3)	0.2107 (2)	0.0292 (5)
C12	0.6507 (3)	1.0573 (3)	0.3241 (2)	0.0335 (6)
H12	0.6119	0.9671	0.3635	0.040*
C13	0.7473 (3)	1.2191 (3)	0.3788 (2)	0.0345 (6)
H13	0.7743	1.2385	0.4561	0.041*
C14	0.8046 (3)	1.3522 (3)	0.3220 (2)	0.0331 (6)
H14	0.8705	1.4616	0.3600	0.040*
C15	0.7642 (3)	1.3232 (3)	0.2090 (2)	0.0301 (5)
C16	0.6671 (3)	1.1633 (3)	0.1528 (2)	0.0331 (5)
H16	0.6386	1.1448	0.0757	0.040*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0187 (8)	0.0236 (10)	0.0286 (10)	−0.0016 (7)	0.0019 (7)	0.0060 (8)
O1	0.0515 (10)	0.0298 (9)	0.0484 (11)	−0.0118 (8)	0.0009 (8)	0.0150 (8)
O2	0.0482 (9)	0.0262 (9)	0.0464 (11)	−0.0139 (7)	−0.0057 (8)	0.0094 (8)
C1	0.0179 (9)	0.0252 (11)	0.0290 (13)	−0.0012 (8)	0.0001 (8)	0.0063 (9)
C2	0.0250 (10)	0.0265 (12)	0.0322 (13)	−0.0015 (9)	−0.0039 (9)	0.0028 (10)
C3	0.0317 (11)	0.0377 (13)	0.0260 (13)	0.0021 (10)	−0.0004 (9)	0.0057 (10)
C4	0.0265 (11)	0.0329 (12)	0.0337 (14)	0.0004 (9)	0.0051 (9)	0.0144 (11)
C5	0.0196 (10)	0.0227 (11)	0.0308 (13)	0.0002 (8)	0.0039 (9)	0.0084 (9)
C6	0.0219 (10)	0.0249 (12)	0.0379 (14)	−0.0007 (8)	0.0021 (9)	0.0092 (10)
C7	0.0447 (13)	0.0281 (12)	0.0378 (15)	−0.0061 (10)	−0.0035 (11)	0.0041 (11)
C8	0.0224 (10)	0.0230 (11)	0.0372 (14)	−0.0009 (8)	0.0005 (9)	0.0083 (10)
C9	0.0431 (13)	0.0334 (13)	0.0348 (14)	−0.0040 (10)	0.0023 (11)	0.0147 (11)
O3	0.0492 (10)	0.0281 (9)	0.0507 (11)	−0.0123 (7)	−0.0084 (8)	0.0123 (8)
O4	0.0503 (10)	0.0290 (9)	0.0481 (11)	−0.0114 (8)	0.0098 (8)	0.0121 (8)
C11	0.0219 (10)	0.0217 (11)	0.0431 (15)	−0.0028 (8)	0.0019 (9)	0.0085 (10)
C12	0.0302 (11)	0.0306 (13)	0.0442 (16)	0.0046 (9)	0.0037 (10)	0.0180 (11)
C13	0.0319 (12)	0.0353 (13)	0.0367 (14)	0.0066 (10)	−0.0023 (10)	0.0077 (11)
C14	0.0267 (11)	0.0250 (12)	0.0454 (16)	0.0010 (9)	−0.0005 (10)	0.0043 (11)
C15	0.0230 (10)	0.0234 (11)	0.0446 (15)	−0.0008 (8)	0.0091 (10)	0.0114 (10)
C16	0.0303 (11)	0.0321 (13)	0.0367 (14)	0.0011 (9)	0.0052 (10)	0.0095 (11)

Geometric parameters (Å, º) top

N1—C5	1.343 (2)	C9—H9A	0.9800
N1—C1	1.349 (3)	C9—H9B	0.9800
O1—C6	1.229 (2)	C9—H9C	0.9800
O2—C8	1.226 (3)	O3—C11	1.371 (3)
C1—C2	1.396 (3)	O3—HO3	0.8400
C1—C8	1.512 (3)	O4—C15	1.377 (2)
C2—C3	1.383 (3)	O4—HO4	0.8400
C2—H2	0.9500	C11—C12	1.392 (3)
C3—C4	1.385 (3)	C11—C16	1.393 (3)
C3—H3	0.9500	C12—C13	1.397 (3)
C4—C5	1.397 (3)	C12—H12	0.9500
C4—H4	0.9500	C13—C14	1.390 (3)
C5—C6	1.505 (3)	C13—H13	0.9500
C6—C7	1.496 (3)	C14—C15	1.389 (3)
C7—H7A	0.9800	C14—H14	0.9500
C7—H7B	0.9800	C15—C16	1.393 (3)
C7—H7C	0.9800	C16—H16	0.9500
C8—C9	1.494 (3)

C5—N1—C1	117.35 (18)	C9—C8—C1	118.19 (19)
N1—C1—C2	122.87 (19)	C8—C9—H9A	109.5
N1—C1—C8	117.01 (19)	C8—C9—H9B	109.5
C2—C1—C8	120.12 (19)	H9A—C9—H9B	109.5
C3—C2—C1	119.2 (2)	C8—C9—H9C	109.5
C3—C2—H2	120.4	H9A—C9—H9C	109.5
C1—C2—H2	120.4	H9B—C9—H9C	109.5
C2—C3—C4	118.4 (2)	C11—O3—HO3	109.5
C2—C3—H3	120.8	C15—O4—HO4	109.5
C4—C3—H3	120.8	O3—C11—C12	122.26 (19)
C3—C4—C5	119.18 (19)	O3—C11—C16	117.1 (2)
C3—C4—H4	120.4	C12—C11—C16	120.7 (2)
C5—C4—H4	120.4	C11—C12—C13	118.9 (2)
N1—C5—C4	122.97 (19)	C11—C12—H12	120.6
N1—C5—C6	116.70 (19)	C13—C12—H12	120.6
C4—C5—C6	120.33 (18)	C14—C13—C12	121.1 (2)
O1—C6—C7	122.1 (2)	C14—C13—H13	119.4
O1—C6—C5	119.5 (2)	C12—C13—H13	119.4
C7—C6—C5	118.45 (18)	C15—C14—C13	119.2 (2)
C6—C7—H7A	109.5	C15—C14—H14	120.4
C6—C7—H7B	109.5	C13—C14—H14	120.4
H7A—C7—H7B	109.5	O4—C15—C14	122.4 (2)
C6—C7—H7C	109.5	O4—C15—C16	116.9 (2)
H7A—C7—H7C	109.5	C14—C15—C16	120.7 (2)
H7B—C7—H7C	109.5	C15—C16—C11	119.4 (2)
O2—C8—C9	122.80 (19)	C15—C16—H16	120.3
O2—C8—C1	119.0 (2)	C11—C16—H16	120.3

C5—N1—C1—C2	−0.9 (3)	N1—C1—C8—O2	−176.44 (19)
C5—N1—C1—C8	179.22 (17)	C2—C1—C8—O2	3.7 (3)
N1—C1—C2—C3	1.7 (3)	N1—C1—C8—C9	3.7 (3)
C8—C1—C2—C3	−178.40 (19)	C2—C1—C8—C9	−176.1 (2)
C1—C2—C3—C4	−0.4 (3)	O3—C11—C12—C13	179.6 (2)
C2—C3—C4—C5	−1.6 (3)	C16—C11—C12—C13	−0.7 (3)
C1—N1—C5—C4	−1.2 (3)	C11—C12—C13—C14	0.1 (3)
C1—N1—C5—C6	178.93 (17)	C12—C13—C14—C15	0.2 (3)
C3—C4—C5—N1	2.5 (3)	C13—C14—C15—O4	179.3 (2)
C3—C4—C5—C6	−177.67 (19)	C13—C14—C15—C16	0.2 (3)
N1—C5—C6—O1	−178.45 (19)	O4—C15—C16—C11	−179.94 (19)
C4—C5—C6—O1	1.7 (3)	C14—C15—C16—C11	−0.8 (3)
N1—C5—C6—C7	0.3 (3)	O3—C11—C16—C15	−179.2 (2)
C4—C5—C6—C7	−179.55 (19)	C12—C11—C16—C15	1.0 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—HO3···O2	0.84	1.95	2.784 (2)	174
O4—HO4···O1ⁱ	0.84	1.96	2.802 (3)	177

Symmetry code: (i) x+1, y+2, z.

Experimental details

Crystal data
Chemical formula	C₉H₉NO₂·C₆H₆O₂
M_r	273.28
Crystal system, space group	Triclinic, P1
Temperature (K)	173
a, b, c (Å)	7.346 (2), 7.866 (2), 12.342 (3)
α, β, γ (°)	101.61 (3), 90.51 (3), 98.72 (3)
V (Å³)	689.9 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.30 × 0.30 × 0.23

Data collection
Diffractometer	Stoe IPDS II two-circle diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	9113, 2515, 1605
R_int	0.094
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.130, 0.93
No. of reflections	2515
No. of parameters	185
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.27

Computer programs: X-AREA (Stoe & Cie, 2001), X-RED32 (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL-Plus (Sheldrick, 2008), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—HO3···O2	0.84	1.95	2.784 (2)	173.6
O4—HO4···O1ⁱ	0.84	1.96	2.802 (3)	176.5

Symmetry code: (i) x+1, y+2, z.

Acknowledgements

We thank Dr Guido Wagner for quantum-mechanical calculations of the relative stability of the 2,6-diacetylpyridine conformations and Professor Dr E. Egert for helpful discussions.

References

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