Crystal structure of 2,2-dimethyl-N-(5-methyl­pyridin-2-yl)propanamide

There are two mol­ecules in the asymmetric unit of the title compound, C₁₁H₁₆N₂O. The pyridine rings and amide groups overlap almost perfectly (r.m.s. overlay fit = 0.053 Å), but the tertiary butyl groups have different orientations: in one mol­ecule, one of the methyl C atoms is syn to the amide O atom [O-C-C-C = -0.8 (3)°] and in the other the equivalent torsion angle is 31.0 (2)°. In the crystal, the two independent mol­ecules are linked by a pair of N-H...N hydrogen bonds in the form of an R₂²(8) loop to form a dimer. A C-H...O inter­action connects the dimers into [100] chains.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.047
• wR factor = 0.148
• Data-to-parameter ratio = 17.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Low       Ueq as Compared to Neighbors for .....         C8 Check
PLAT242_ALERT_2_C Low       Ueq as Compared to Neighbors for .....        C18 Check
PLAT242_ALERT_2_C Low       Ueq as Compared to Neighbors for .....        C19 Check
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600         19 Report
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          1 Note

Alert level G
PLAT007_ALERT_5_G Number of Unrefined Donor-H Atoms ..............          2 Report
PLAT790_ALERT_4_G Centre of Gravity not Within Unit Cell: Resd.  #          2 Note
              C11 H16 N2 O
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600        155 Note

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   5 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Introduction

Substituted pyridines are important compounds (Joule & Mills, 2000) and show a range of biological activities (de Candia et al., 2013; Abdel-Megeed et al., 2012). The pyridine ring system has been modified using various efficient and simple procedures that include the use of lithium reagents as inter­mediates (El-Hiti et al., 2015; Smith et al., 2013, Smith et al., 2012; Turner, 1983). The X-ray crystal structures of related compounds have been reported (El-Hiti et al., 2015; El-Hiti et al., 2014; Seidler et al., 2011; Koch et al., 2008).

S2. Experimental

S2.1. Synthesis and crystallization

2,2-Di­methyl-N-(5-methyl­pyridin-2-yl)propanamide was obtained in 83% yield from reaction of 2-amino-5-methyl­pyridine with tri­methyl­acetyl chloride in the presence of tri­ethyl­amine in di­chloro­methane at 0 °C for 15 minutes and then at room temperature for 2 h (Turner, 1983). The crude product was purified by column chromatography (silica gel; di­chloro­methane) followed by crystallization from hexane to give colourless crystals of the title compound. The NMR spectral data and elemental analyses for the title compound were identical with those previously reported (Turner, 1983).

S2.2. Refinement

H atoms were positioned geometrically and refined using a riding model with U_iso(H) constrained to be 1.2 times U_eq for the atom it is bonded to except for methyl groups where it was 1.5 times with free rotation about the C—C bond.

S3. Results and discussion

The asymmetric unit (Figure 1) consists of two independent molecules of C₁₁H₁₆N₂O. The amide group and pyridine ring within the molecule are not co-planar as indicated by the torsion angles [N1—C1—N2—C7 = 142.20 (14), N3—C12—N4—C18 = 148.58 (15)]. The two independent molecules are linked by a pair of N—H···N hydrogen bonds (Table 1, Figure 2) to form an R₂²(8) ring.

Related literature

For the synthesis and spectroscopic data, see: Turner (1983). For related compounds, see: El-Hiti et al. (2015a,b); de Candia et al. (2013); Smith et al. (2013, 2012); Abdel-Megeed et al. (2012). Joule & Mills (2000). For the crystal structures of related compounds, see: El-Hiti et al. (2014); Seidler et al. (2011); Koch et al. (2008).

Computing details

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2015); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures

	Fig. 1. The asymmetric unit of C11H16N2O with 50% probability displacement ellipsoids for nonhydrogen atoms.
	Fig. 2. The asymmetric unit showing N—H···N interactions as dotted lines.

2,2-Dimethyl-N-(5-methylpyridin-2-yl)propanamide

Crystal data

C11H16N2O	F(000) = 832
Mr = 192.26	Dx = 1.108 Mg m^−3
Monoclinic, P21/n	Cu Kα radiation, λ = 1.54184 Å
a = 11.1969 (2) Å	Cell parameters from 3890 reflections
b = 8.6439 (2) Å	θ = 3.9–73.6°
c = 23.8844 (5) Å	µ = 0.57 mm^−1
β = 94.549 (2)°	T = 296 K
V = 2304.37 (8) Å^3	Plate, colourless
Z = 8	0.47 × 0.33 × 0.11 mm

Data collection

Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer	4503 independent reflections
Radiation source: sealed X-ray tube, SuperNova (Cu) X-ray Source	3684 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.021
ω scans	θmax = 74.0°, θmin = 3.7°
Absorption correction: gaussian (CrysAlis PRO; Agilent, 2014)	h = −13→13
Tmin = 0.925, Tmax = 0.975	k = −9→10
8391 measured reflections	l = −29→24

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.047	w = 1/[σ^2(Fo^2) + (0.081P)^2 + 0.208P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.148	(Δ/σ)max < 0.001
S = 1.04	Δρmax = 0.27 e Å^−3
4503 reflections	Δρmin = −0.21 e Å^−3
262 parameters	Extinction correction: SHELXL2013 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0075 (6)

Special details

Experimental. Absorption correction: CrysAlisPro, Agilent Technologies, Version 1.171.37.33 (release 27-03-2014 CrysAlis171 .NET) (compiled Mar 27 2014,17:12:48) Numerical absorption correction based on gaussian integration over a multifaceted crystal model Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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.

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

	x	y	z	Uiso*/Ueq
C1	0.20122 (11)	0.54209 (16)	0.13526 (5)	0.0525 (3)
C2	0.19343 (14)	0.77138 (18)	0.08875 (7)	0.0650 (4)
H2	0.1480	0.8535	0.0736	0.097*
C3	0.31560 (14)	0.77581 (19)	0.08401 (7)	0.0670 (4)
C4	0.38057 (13)	0.6528 (2)	0.10739 (7)	0.0701 (4)
H4	0.4632	0.6499	0.1055	0.105*
C5	0.32450 (12)	0.5351 (2)	0.13327 (7)	0.0654 (4)
H5	0.3681	0.4524	0.1492	0.098*
C6	0.3730 (2)	0.9087 (3)	0.05543 (12)	0.1036 (7)
H6A	0.4566	0.9132	0.0677	0.155*
H6B	0.3349	1.0037	0.0649	0.155*
H6C	0.3639	0.8939	0.0155	0.155*
C7	0.15945 (14)	0.27433 (18)	0.16115 (6)	0.0618 (4)
C8	0.07563 (15)	0.16852 (19)	0.19135 (7)	0.0689 (4)
C9	0.1450 (2)	0.0226 (2)	0.21008 (9)	0.0942 (6)
H9A	0.1777	−0.0243	0.1782	0.141*
H9B	0.0920	−0.0490	0.2263	0.141*
H9C	0.2090	0.0496	0.2375	0.141*
C10	0.0273 (2)	0.2443 (2)	0.24272 (9)	0.0918 (6)
H10A	−0.0163	0.1692	0.2626	0.138*
H10B	−0.0250	0.3280	0.2309	0.138*
H10C	0.0929	0.2832	0.2670	0.138*
C11	−0.0263 (2)	0.1254 (3)	0.14762 (12)	0.1106 (8)
H11A	0.0066	0.0838	0.1149	0.166*
H11B	−0.0726	0.2160	0.1374	0.166*
H11C	−0.0768	0.0494	0.1631	0.166*
C12	−0.12246 (11)	0.71207 (16)	0.19991 (6)	0.0520 (3)
C13	−0.02137 (14)	0.65237 (19)	0.28397 (6)	0.0650 (4)
H13	0.0409	0.5995	0.3037	0.098*
C14	−0.09434 (14)	0.74294 (19)	0.31429 (6)	0.0634 (4)
C15	−0.18413 (15)	0.8222 (2)	0.28376 (7)	0.0710 (4)
H15	−0.2350	0.8861	0.3023	0.106*
C16	−0.19970 (14)	0.8082 (2)	0.22610 (7)	0.0660 (4)
H16	−0.2603	0.8618	0.2054	0.099*
C17	−0.0774 (2)	0.7526 (3)	0.37741 (7)	0.0909 (6)
H17A	−0.0997	0.8538	0.3894	0.136*
H17B	0.0051	0.7335	0.3895	0.136*
H17C	−0.1268	0.6765	0.3936	0.136*
C18	−0.22818 (13)	0.6925 (2)	0.10586 (6)	0.0671 (4)
C19	−0.21118 (14)	0.6626 (2)	0.04398 (6)	0.0714 (4)
C20	−0.1518 (2)	0.5048 (3)	0.03776 (9)	0.1036 (7)
H20A	−0.0736	0.5054	0.0575	0.155*
H20B	−0.1445	0.4838	−0.0013	0.155*
H20C	−0.1999	0.4260	0.0532	0.155*
C21	−0.1325 (2)	0.7892 (3)	0.02172 (9)	0.1074 (8)
H21A	−0.1659	0.8887	0.0293	0.161*
H21B	−0.1291	0.7767	−0.0181	0.161*
H21C	−0.0532	0.7819	0.0400	0.161*
C22	−0.33408 (17)	0.6641 (3)	0.01113 (8)	0.0955 (7)
H22A	−0.3810	0.5790	0.0230	0.143*
H22B	−0.3242	0.6546	−0.0283	0.143*
H22C	−0.3742	0.7596	0.0180	0.143*
N1	0.13561 (10)	0.65829 (14)	0.11338 (5)	0.0578 (3)
N2	0.13689 (10)	0.42840 (14)	0.16285 (5)	0.0577 (3)
H2A	0.0795	0.4589	0.1821	0.086*
N3	−0.03374 (10)	0.63507 (14)	0.22795 (5)	0.0589 (3)
N4	−0.12739 (10)	0.69100 (15)	0.14133 (5)	0.0585 (3)
H4A	−0.0606	0.6758	0.1267	0.088*
O1	0.23876 (14)	0.22212 (15)	0.13479 (7)	0.0942 (4)
O2	−0.32545 (10)	0.7145 (3)	0.12290 (6)	0.1234 (7)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0471 (6)	0.0604 (7)	0.0506 (6)	−0.0005 (5)	0.0069 (5)	−0.0061 (5)
C2	0.0609 (8)	0.0606 (8)	0.0750 (9)	0.0020 (6)	0.0152 (7)	0.0019 (7)
C3	0.0619 (8)	0.0670 (9)	0.0739 (9)	−0.0103 (7)	0.0180 (7)	−0.0082 (7)
C4	0.0458 (7)	0.0872 (11)	0.0783 (10)	−0.0058 (7)	0.0111 (6)	−0.0054 (8)
C5	0.0476 (7)	0.0792 (10)	0.0695 (9)	0.0046 (7)	0.0061 (6)	0.0024 (7)
C6	0.0929 (14)	0.0845 (13)	0.139 (2)	−0.0182 (11)	0.0419 (13)	0.0105 (12)
C7	0.0633 (8)	0.0634 (8)	0.0595 (8)	0.0033 (7)	0.0093 (6)	−0.0058 (6)
C8	0.0743 (10)	0.0600 (8)	0.0730 (9)	−0.0017 (7)	0.0096 (8)	0.0039 (7)
C9	0.1260 (17)	0.0716 (11)	0.0864 (12)	0.0159 (11)	0.0172 (12)	0.0096 (9)
C10	0.1089 (15)	0.0753 (11)	0.0977 (13)	0.0020 (10)	0.0486 (12)	0.0135 (10)
C11	0.0982 (15)	0.1086 (17)	0.1210 (18)	−0.0325 (13)	−0.0168 (14)	0.0207 (14)
C12	0.0441 (6)	0.0584 (7)	0.0541 (7)	−0.0037 (5)	0.0082 (5)	−0.0028 (5)
C13	0.0649 (8)	0.0748 (9)	0.0553 (8)	0.0084 (7)	0.0041 (6)	0.0003 (7)
C14	0.0628 (8)	0.0718 (9)	0.0566 (8)	−0.0045 (7)	0.0101 (6)	−0.0074 (6)
C15	0.0643 (9)	0.0830 (10)	0.0672 (9)	0.0103 (8)	0.0145 (7)	−0.0160 (8)
C16	0.0574 (8)	0.0769 (9)	0.0643 (8)	0.0125 (7)	0.0078 (6)	−0.0056 (7)
C17	0.0947 (13)	0.1195 (16)	0.0590 (9)	0.0039 (12)	0.0092 (9)	−0.0124 (10)
C18	0.0479 (7)	0.0957 (11)	0.0581 (8)	−0.0060 (7)	0.0062 (6)	−0.0059 (7)
C19	0.0574 (8)	0.1030 (12)	0.0540 (8)	−0.0056 (8)	0.0058 (6)	−0.0037 (8)
C20	0.1021 (15)	0.1323 (18)	0.0765 (12)	0.0172 (14)	0.0078 (10)	−0.0312 (12)
C21	0.0894 (13)	0.161 (2)	0.0718 (11)	−0.0318 (14)	0.0046 (10)	0.0262 (13)
C22	0.0681 (10)	0.153 (2)	0.0636 (10)	−0.0080 (12)	−0.0058 (8)	−0.0082 (11)
N1	0.0483 (6)	0.0612 (6)	0.0649 (7)	0.0024 (5)	0.0111 (5)	−0.0014 (5)
N2	0.0517 (6)	0.0616 (7)	0.0612 (6)	0.0020 (5)	0.0141 (5)	0.0003 (5)
N3	0.0564 (6)	0.0654 (7)	0.0555 (6)	0.0082 (5)	0.0078 (5)	−0.0030 (5)
N4	0.0464 (6)	0.0772 (8)	0.0526 (6)	0.0019 (5)	0.0081 (5)	−0.0045 (5)
O1	0.1027 (10)	0.0738 (8)	0.1127 (10)	0.0100 (7)	0.0496 (8)	−0.0114 (7)
O2	0.0451 (6)	0.250 (2)	0.0754 (8)	−0.0005 (9)	0.0067 (5)	−0.0370 (11)

Geometric parameters (Å, º)

C1—N1	1.3269 (18)	C12—C16	1.384 (2)
C1—C5	1.3862 (19)	C12—N4	1.4077 (17)
C1—N2	1.4122 (17)	C13—N3	1.3427 (19)
C2—N1	1.3346 (19)	C13—C14	1.378 (2)
C2—C3	1.382 (2)	C13—H13	0.9300
C2—H2	0.9300	C14—C15	1.377 (2)
C3—C4	1.381 (2)	C14—C17	1.507 (2)
C3—C6	1.506 (2)	C15—C16	1.380 (2)
C4—C5	1.368 (2)	C15—H15	0.9300
C4—H4	0.9300	C16—H16	0.9300
C5—H5	0.9300	C17—H17A	0.9600
C6—H6A	0.9600	C17—H17B	0.9600
C6—H6B	0.9600	C17—H17C	0.9600
C6—H6C	0.9600	C18—O2	1.208 (2)
C7—O1	1.2155 (19)	C18—N4	1.3565 (19)
C7—N2	1.3567 (19)	C18—C19	1.527 (2)
C7—C8	1.531 (2)	C19—C21	1.526 (3)
C8—C10	1.527 (3)	C19—C22	1.529 (2)
C8—C9	1.529 (3)	C19—C20	1.531 (3)
C8—C11	1.531 (3)	C20—H20A	0.9600
C9—H9A	0.9600	C20—H20B	0.9600
C9—H9B	0.9600	C20—H20C	0.9600
C9—H9C	0.9600	C21—H21A	0.9600
C10—H10A	0.9600	C21—H21B	0.9600
C10—H10B	0.9600	C21—H21C	0.9600
C10—H10C	0.9600	C22—H22A	0.9600
C11—H11A	0.9600	C22—H22B	0.9600
C11—H11B	0.9600	C22—H22C	0.9600
C11—H11C	0.9600	N2—H2A	0.8600
C12—N3	1.3314 (18)	N4—H4A	0.8600
N1—C1—C5	122.76 (13)	N3—C13—H13	117.7
N1—C1—N2	115.06 (11)	C14—C13—H13	117.7
C5—C1—N2	122.13 (13)	C15—C14—C13	116.30 (14)
N1—C2—C3	125.05 (15)	C15—C14—C17	122.08 (15)
N1—C2—H2	117.5	C13—C14—C17	121.62 (16)
C3—C2—H2	117.5	C14—C15—C16	120.94 (14)
C4—C3—C2	116.01 (14)	C14—C15—H15	119.5
C4—C3—C6	122.73 (16)	C16—C15—H15	119.5
C2—C3—C6	121.25 (17)	C15—C16—C12	118.01 (14)
C5—C4—C3	120.60 (14)	C15—C16—H16	121.0
C5—C4—H4	119.7	C12—C16—H16	121.0
C3—C4—H4	119.7	C14—C17—H17A	109.5
C4—C5—C1	118.49 (15)	C14—C17—H17B	109.5
C4—C5—H5	120.8	H17A—C17—H17B	109.5
C1—C5—H5	120.8	C14—C17—H17C	109.5
C3—C6—H6A	109.5	H17A—C17—H17C	109.5
C3—C6—H6B	109.5	H17B—C17—H17C	109.5
H6A—C6—H6B	109.5	O2—C18—N4	121.25 (14)
C3—C6—H6C	109.5	O2—C18—C19	122.54 (14)
H6A—C6—H6C	109.5	N4—C18—C19	116.20 (13)
H6B—C6—H6C	109.5	C21—C19—C18	109.61 (16)
O1—C7—N2	121.70 (15)	C21—C19—C22	109.63 (17)
O1—C7—C8	121.50 (15)	C18—C19—C22	108.60 (14)
N2—C7—C8	116.72 (13)	C21—C19—C20	109.78 (18)
C10—C8—C9	108.82 (16)	C18—C19—C20	109.45 (16)
C10—C8—C11	111.11 (19)	C22—C19—C20	109.75 (18)
C9—C8—C11	109.45 (17)	C19—C20—H20A	109.5
C10—C8—C7	113.06 (14)	C19—C20—H20B	109.5
C9—C8—C7	108.31 (15)	H20A—C20—H20B	109.5
C11—C8—C7	106.00 (15)	C19—C20—H20C	109.5
C8—C9—H9A	109.5	H20A—C20—H20C	109.5
C8—C9—H9B	109.5	H20B—C20—H20C	109.5
H9A—C9—H9B	109.5	C19—C21—H21A	109.5
C8—C9—H9C	109.5	C19—C21—H21B	109.5
H9A—C9—H9C	109.5	H21A—C21—H21B	109.5
H9B—C9—H9C	109.5	C19—C21—H21C	109.5
C8—C10—H10A	109.5	H21A—C21—H21C	109.5
C8—C10—H10B	109.5	H21B—C21—H21C	109.5
H10A—C10—H10B	109.5	C19—C22—H22A	109.5
C8—C10—H10C	109.5	C19—C22—H22B	109.5
H10A—C10—H10C	109.5	H22A—C22—H22B	109.5
H10B—C10—H10C	109.5	C19—C22—H22C	109.5
C8—C11—H11A	109.5	H22A—C22—H22C	109.5
C8—C11—H11B	109.5	H22B—C22—H22C	109.5
H11A—C11—H11B	109.5	C1—N1—C2	117.08 (12)
C8—C11—H11C	109.5	C7—N2—C1	124.47 (12)
H11A—C11—H11C	109.5	C7—N2—H2A	117.8
H11B—C11—H11C	109.5	C1—N2—H2A	117.8
N3—C12—C16	122.75 (13)	C12—N3—C13	117.35 (12)
N3—C12—N4	113.83 (11)	C18—N4—C12	125.79 (12)
C16—C12—N4	123.38 (13)	C18—N4—H4A	117.1
N3—C13—C14	124.64 (14)	C12—N4—H4A	117.1
N1—C2—C3—C4	−0.6 (3)	O2—C18—C19—C21	119.0 (2)
N1—C2—C3—C6	−179.97 (18)	N4—C18—C19—C21	−61.9 (2)
C2—C3—C4—C5	0.2 (2)	O2—C18—C19—C22	−0.8 (3)
C6—C3—C4—C5	179.56 (18)	N4—C18—C19—C22	178.35 (18)
C3—C4—C5—C1	0.3 (2)	O2—C18—C19—C20	−120.6 (2)
N1—C1—C5—C4	−0.3 (2)	N4—C18—C19—C20	58.5 (2)
N2—C1—C5—C4	−177.72 (14)	C5—C1—N1—C2	0.0 (2)
O1—C7—C8—C10	151.67 (19)	N2—C1—N1—C2	177.54 (12)
N2—C7—C8—C10	−31.6 (2)	C3—C2—N1—C1	0.5 (2)
O1—C7—C8—C9	31.0 (2)	O1—C7—N2—C1	−0.2 (2)
N2—C7—C8—C9	−152.30 (15)	C8—C7—N2—C1	−176.94 (13)
O1—C7—C8—C11	−86.4 (2)	N1—C1—N2—C7	142.20 (14)
N2—C7—C8—C11	90.33 (19)	C5—C1—N2—C7	−40.2 (2)
N3—C13—C14—C15	−1.3 (3)	C16—C12—N3—C13	0.6 (2)
N3—C13—C14—C17	177.95 (17)	N4—C12—N3—C13	178.41 (13)
C13—C14—C15—C16	0.9 (3)	C14—C13—N3—C12	0.5 (2)
C17—C14—C15—C16	−178.27 (18)	O2—C18—N4—C12	0.7 (3)
C14—C15—C16—C12	0.1 (3)	C19—C18—N4—C12	−178.44 (15)
N3—C12—C16—C15	−0.9 (2)	N3—C12—N4—C18	148.58 (15)
N4—C12—C16—C15	−178.46 (15)	C16—C12—N4—C18	−33.7 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···N3	0.86	2.31	3.1192 (16)	156
N4—H4A···N1	0.86	2.25	3.0837 (16)	163
C4—H4···O2^i	0.93	2.43	3.3262 (19)	160

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