1-(6-Methyl­pyridin-2-yl)-2-phenyl­ethanedione

The phenyl and pyridyl rings of the title compound, C₁₄H₁₁NO₂, are nearly perpendicular to each other, with a dihedral angle of 86.1 (1)°. In the crystal, the mol­ecules exist as centrosymmetrically hydrogen-bonded C—H...O dimers and the molecular packing is stabilized by C—H...π and π...π interactions.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.066
• wR factor = 0.153
• Data-to-parameter ratio = 12.9

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



PLAT_369  Alert C Long   C(sp2)-C(sp2) Bond  C(6)   -   C(7)   =       1.54 Ang.


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

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S1. Comment

Recently, we have investigated photo-induced oxygenation reactions of indolizine derivatives (Tian et al., 2001). In a continuation of this work, we report here the crystal structure of the title compound, (I), which was obtained by photo-induced oxygenation of 1-benzoyl-5-methyl-2-phenylindolizine in acetonitrile.

The bond lengths in the title compound (Fig. 1) are comparable to the mean values reported by Allen et al. (1987). The C6—C7 distance of 1.536 (3) Å is significantly longer than the value of 1.48 Å expected for a Csp²—Csp² bond. This lengthening may be due to the repulsion between the two O atoms. The two aromatic rings, phenyl and pyridine rings, are nearly orthogonal, with a dihedral angle of 86.1 (1)°. In the solid state, the molecules form centrosymmetrically C4—H4···O1ⁱ [symmetry code: (i) = −x, 2 − y, −z] hydrogen-bonded dimers (Table 1). Weak intermolecular C2—H2···π_phenyl interactions link the dimers to form infinite one-dimensional molecular chains parallel to (110) (Fig. 2). The crystal packing is further stabilized by π···π stacking interactions involving the pyridine and its symmetry equivalent at (-x, 1 − y, −z) [centroid separation 3.659 (1) Å].

S2. Experimental

The title compound was isolated from the reaction mixture, obtained by the photo-oxygenation of 1-benzoyl-5-methyl-2-phenylindolizine in acetonitrile, by column chromatography on silica gel. Single crystals suitable for X-ray crystallographic measurement were grown by slow evaporation of a petroleum ether-ethyl acetate solution (5:1 v/v) of the compound.

S3. Refinement

The H atoms of the aromatic rings were located from a difference Fourier map and were refined isotropically; those attached to the methyl C14 were fixed geometrically and treated as riding atoms, with C—H distances of 0.96 Å and U_iso(H) set equal to 1.5U_eq(C). Owing to a large fraction of weak data at higher angles, the 2θ maximum was limited to 54° during the refinement.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT and SADABS (Sheldrick, 1996); program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 1990).

Figures

	Fig. 1. The structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. Arrangement of hydrogen-bonded dimers, viewed normal to (110).

1-(6-Methylpyridin-2-yl)-2-phenylethanedione

Crystal data

C14H11NO2	Z = 2
Mr = 225.24	F(000) = 236
Triclinic, P1	Dx = 1.310 Mg m^−3
Hall symbol: -P 1	Melting point: 350(1)K K
a = 7.9526 (9) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.0441 (10) Å	Cell parameters from 1413 reflections
c = 9.1229 (11) Å	θ = 2.5–28.3°
α = 90.953 (2)°	µ = 0.09 mm^−1
β = 101.247 (2)°	T = 293 K
γ = 93.647 (2)°	Slab, pale yellow
V = 570.99 (12) Å^3	0.50 × 0.42 × 0.10 mm

Data collection

Siemens SMART CCD area detector diffractometer	1820 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.011
Graphite monochromator	θmax = 27.0°, θmin = 2.5°
Detector resolution: 8.33 pixels mm^-1	h = −10→9
ω scans	k = −10→9
3296 measured reflections	l = −11→11
2408 independent reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.066	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.153	H atoms treated by a mixture of independent and constrained refinement
S = 1.15	w = 1/[σ^2(Fo^2) + (0.0543P)^2 + 0.2157P] where P = (Fo^2 + 2Fc^2)/3
2408 reflections	(Δ/σ)max < 0.001
187 parameters	Δρmax = 0.22 e Å^−3
0 restraints	Δρmin = −0.27 e Å^−3

Special details

Experimental. The data collection covered over a hemisphere of reciprocal space by a combination of three sets of exposures; each set had a different ϕ angle (0, 88 and 180°) for the crystal and each exposure of 10 s covered 0.3° in ω. The crystal-to-detector distance was 5 cm and the detector swing angle was −35°. Crystal decay was monitored by repeating fifty initial frames at the end of data collection and analysing the intensity of duplicate reflections, and was found to be negligible.

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.0776 (3)	0.9106 (2)	0.1841 (2)	0.0731 (6)
O2	0.1615 (2)	0.6692 (2)	0.42875 (19)	0.0646 (5)
N1	0.2555 (2)	0.5407 (2)	0.10166 (18)	0.0414 (4)
C1	0.2743 (3)	0.4382 (3)	−0.0108 (2)	0.0440 (5)
C2	0.2237 (3)	0.4800 (3)	−0.1595 (3)	0.0556 (6)
H2	0.243 (3)	0.401 (3)	−0.233 (3)	0.062 (7)*
C3	0.1502 (3)	0.6274 (4)	−0.1943 (3)	0.0578 (7)
H3	0.113 (3)	0.658 (3)	−0.297 (3)	0.068 (8)*
C4	0.1258 (3)	0.7324 (3)	−0.0802 (3)	0.0499 (6)
H4	0.078 (3)	0.833 (3)	−0.094 (3)	0.050 (7)*
C5	0.1817 (3)	0.6842 (3)	0.0652 (2)	0.0408 (5)
C6	0.1616 (3)	0.7896 (3)	0.1950 (2)	0.0465 (6)
C7	0.2508 (3)	0.7381 (3)	0.3509 (2)	0.0444 (5)
C8	0.4364 (3)	0.7800 (3)	0.3982 (2)	0.0408 (5)
C9	0.5270 (3)	0.7074 (3)	0.5248 (3)	0.0513 (6)
H9	0.464 (3)	0.633 (3)	0.579 (3)	0.062 (8)*
C10	0.7019 (4)	0.7391 (4)	0.5670 (3)	0.0604 (7)
H10	0.764 (4)	0.681 (4)	0.657 (3)	0.081 (9)*
C11	0.7882 (4)	0.8452 (4)	0.4860 (3)	0.0627 (7)
H11	0.908 (4)	0.869 (3)	0.515 (3)	0.074 (9)*
C12	0.6999 (4)	0.9220 (3)	0.3632 (3)	0.0587 (7)
H12	0.753 (3)	1.000 (3)	0.304 (3)	0.056 (7)*
C13	0.5240 (3)	0.8883 (3)	0.3185 (3)	0.0490 (6)
H13	0.464 (3)	0.945 (3)	0.234 (3)	0.055 (7)*
C14	0.3501 (4)	0.2755 (3)	0.0323 (3)	0.0623 (7)
H14A	0.4281	0.2897	0.1269	0.093*
H14B	0.4109	0.2398	−0.0425	0.093*
H14C	0.2598	0.1931	0.0400	0.093*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0846 (14)	0.0685 (12)	0.0653 (12)	0.0379 (11)	0.0030 (10)	−0.0060 (9)
O2	0.0581 (11)	0.0885 (14)	0.0498 (10)	−0.0025 (10)	0.0198 (8)	0.0018 (9)
N1	0.0421 (10)	0.0462 (11)	0.0364 (9)	0.0030 (8)	0.0089 (8)	0.0016 (8)
C1	0.0431 (13)	0.0465 (13)	0.0426 (12)	−0.0024 (10)	0.0110 (9)	−0.0044 (9)
C2	0.0608 (16)	0.0646 (16)	0.0417 (13)	0.0000 (13)	0.0133 (11)	−0.0111 (12)
C3	0.0572 (16)	0.0789 (19)	0.0348 (12)	0.0018 (13)	0.0037 (11)	0.0047 (12)
C4	0.0457 (14)	0.0588 (16)	0.0445 (13)	0.0086 (12)	0.0053 (10)	0.0082 (11)
C5	0.0358 (11)	0.0465 (13)	0.0397 (11)	0.0011 (9)	0.0066 (9)	0.0022 (9)
C6	0.0452 (13)	0.0470 (13)	0.0474 (13)	0.0089 (10)	0.0076 (10)	−0.0018 (10)
C7	0.0529 (14)	0.0470 (13)	0.0363 (11)	0.0097 (10)	0.0149 (10)	−0.0070 (9)
C8	0.0469 (13)	0.0397 (11)	0.0364 (11)	0.0082 (9)	0.0090 (9)	−0.0081 (9)
C9	0.0597 (16)	0.0493 (14)	0.0438 (13)	0.0069 (12)	0.0063 (11)	0.0004 (10)
C10	0.0593 (17)	0.0622 (16)	0.0553 (15)	0.0139 (13)	−0.0020 (13)	−0.0025 (12)
C11	0.0473 (17)	0.0641 (17)	0.0728 (19)	0.0028 (13)	0.0046 (14)	−0.0186 (14)
C12	0.0645 (18)	0.0509 (15)	0.0637 (16)	−0.0051 (13)	0.0235 (14)	−0.0066 (12)
C13	0.0612 (16)	0.0440 (13)	0.0428 (13)	0.0075 (11)	0.0114 (11)	−0.0018 (10)
C14	0.0762 (19)	0.0535 (15)	0.0599 (15)	0.0097 (13)	0.0186 (14)	−0.0029 (12)

Geometric parameters (Å, º)

O1—C6	1.210 (3)	C8—C13	1.383 (3)
O2—C7	1.215 (3)	C8—C9	1.395 (3)
N1—C1	1.342 (3)	C9—C10	1.375 (4)
N1—C5	1.346 (3)	C9—H9	0.96 (3)
C1—C2	1.391 (3)	C10—C11	1.375 (4)
C1—C14	1.502 (3)	C10—H10	1.01 (3)
C2—C3	1.369 (4)	C11—C12	1.378 (4)
C2—H2	0.96 (3)	C11—H11	0.94 (3)
C3—C4	1.380 (4)	C12—C13	1.387 (4)
C3—H3	0.97 (3)	C12—H12	0.96 (2)
C4—C5	1.384 (3)	C13—H13	0.96 (2)
C4—H4	0.92 (2)	C14—H14A	0.96
C5—C6	1.485 (3)	C14—H14B	0.96
C6—C7	1.536 (3)	C14—H14C	0.96
C7—C8	1.471 (3)
C1—N1—C5	117.45 (18)	C13—C8—C7	121.4 (2)
N1—C1—C2	121.5 (2)	C9—C8—C7	119.5 (2)
N1—C1—C14	116.59 (19)	C10—C9—C8	120.4 (3)
C2—C1—C14	121.9 (2)	C10—C9—H9	121.6 (15)
C3—C2—C1	120.1 (2)	C8—C9—H9	118.0 (15)
C3—C2—H2	123.3 (15)	C9—C10—C11	120.1 (3)
C1—C2—H2	116.6 (15)	C9—C10—H10	118.0 (17)
C2—C3—C4	119.1 (2)	C11—C10—H10	121.9 (17)
C2—C3—H3	121.1 (16)	C10—C11—C12	120.3 (3)
C4—C3—H3	119.8 (16)	C10—C11—H11	120.6 (17)
C3—C4—C5	117.6 (2)	C12—C11—H11	119.1 (17)
C3—C4—H4	124.8 (15)	C11—C12—C13	119.9 (3)
C5—C4—H4	117.6 (15)	C11—C12—H12	124.0 (15)
N1—C5—C4	124.1 (2)	C13—C12—H12	116.1 (15)
N1—C5—C6	114.53 (18)	C8—C13—C12	120.2 (2)
C4—C5—C6	121.4 (2)	C8—C13—H13	121.0 (15)
O1—C6—C5	123.6 (2)	C12—C13—H13	118.8 (15)
O1—C6—C7	119.1 (2)	C1—C14—H14A	109.5
C5—C6—C7	117.26 (19)	C1—C14—H14B	109.5
O2—C7—C8	124.3 (2)	H14A—C14—H14B	109.5
O2—C7—C6	117.4 (2)	C1—C14—H14C	109.5
C8—C7—C6	118.3 (2)	H14A—C14—H14C	109.5
C13—C8—C9	119.1 (2)	H14B—C14—H14C	109.5
C5—N1—C1—C2	1.6 (3)	C5—C6—C7—O2	−103.1 (2)
C5—N1—C1—C14	−177.5 (2)	O1—C6—C7—C8	−102.2 (3)
N1—C1—C2—C3	−1.0 (4)	C5—C6—C7—C8	78.9 (3)
C14—C1—C2—C3	178.0 (2)	O2—C7—C8—C13	−166.2 (2)
C1—C2—C3—C4	−0.6 (4)	C6—C7—C8—C13	11.6 (3)
C2—C3—C4—C5	1.6 (4)	O2—C7—C8—C9	14.8 (3)
C1—N1—C5—C4	−0.6 (3)	C6—C7—C8—C9	−167.4 (2)
C1—N1—C5—C6	178.75 (19)	C13—C8—C9—C10	−1.9 (3)
C3—C4—C5—N1	−1.1 (4)	C7—C8—C9—C10	177.0 (2)
C3—C4—C5—C6	179.7 (2)	C8—C9—C10—C11	1.2 (4)
N1—C5—C6—O1	−169.4 (2)	C9—C10—C11—C12	0.8 (4)
C4—C5—C6—O1	9.9 (4)	C10—C11—C12—C13	−1.9 (4)
N1—C5—C6—C7	9.4 (3)	C9—C8—C13—C12	0.8 (3)
C4—C5—C6—C7	−171.3 (2)	C7—C8—C13—C12	−178.2 (2)
O1—C6—C7—O2	75.7 (3)	C11—C12—C13—C8	1.1 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···O1^i	0.92 (2)	2.54 (2)	3.442 (3)	169 (2)
C2—H2···Cg(phenyl)^ii	0.96 (3)	2.99 (4)	3.931 (4)	167 (2)

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