3-Oxocyclo-butane-carboxylic acid: hydrogen bonding in a small-ring γ-keto acid.

The title ketocarboxylic acid, C(5)H(6)O(3), is the smallest carboxy-cyclanone to have its crystal structure determined. It adopts a chiral conformation, by rotation of its carboxyl O atoms away from the plane of skeletal symmetry that passes through the carboxyl carbon and both atoms of the ketone carbonyl. The four-membered ring is non-planar, with a shallow fold of 14.3 (1)° along a line connecting the two α-carbons of the ketone group. In the crystal, the molecules are linked by centrosymmetric hydrogen-bond pairing of ordered carboxylic acid groups [O⋯O = 2.6392 (12) Å and O-H⋯O = 175.74 (15)°], yielding two different sets of dimers, related by by a 2(1) screw axis in c, in the cell. A C-H⋯O interaction is also present.

Related literature

For related structures, see: Barcon et al. (1999 ▶); Borthwick (1980 ▶); Harata et al. (1977 ▶); Malak et al. (2006 ▶); Meiboom & Snyder (1967 ▶); Pigou & Schiesser (1988 ▶). For hydrogen bonding, see: Steiner (1997 ▶).

Experimental

Crystal data

C5H6O3

M = 114.10

Monoclinic,

a = 8.8858 (19) Å

b = 5.3631 (12) Å

c = 11.625 (3) Å

β = 106.899 (4)°

V = 530.1 (2) Å3

Z = 4

Cu Kα radiation

μ = 1.03 mm−1

T = 100 (2) K

0.48 × 0.20 × 0.15 mm

Data collection

Bruker SMART CCD APEXII area-detector diffractometer

Absorption correction: numerical (SADABS; Sheldrick, 2008 ▶) T min = 0.638, T max = 0.861

3854 measured reflections

906 independent reflections

891 reflections with I > 2σ(I)

R int = 0.019

Refinement

R[F 2 > 2σ(F 2)] = 0.029

wR(F 2) = 0.070

S = 1.06

906 reflections

77 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.25 e Å−3

Δρmin = −0.17 e Å−3

Data collection: APEX2 (Bruker, 2006 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809003961/fl2232sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809003961/fl2232Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C5H6O3	F(000) = 240
Mr = 114.10	Dx = 1.430 Mg m−3
Monoclinic, P21/c	Melting point: 342 K
Hall symbol: -P 2ybc	Cu Kα radiation, λ = 1.54178 Å
a = 8.8858 (19) Å	Cell parameters from 3724 reflections
b = 5.3631 (12) Å	θ = 4.0–66.7°
c = 11.625 (3) Å	µ = 1.03 mm−1
β = 106.899 (4)°	T = 100 K
V = 530.1 (2) Å3	Parallelepiped, colourless
Z = 4	0.48 × 0.20 × 0.15 mm

Bruker SMART CCD APEXII area-detector diffractometer	906 independent reflections
Radiation source: fine-focus sealed tube	891 reflections with I > 2σ(I)
graphite	Rint = 0.019
φ and ω scans	θmax = 66.7°, θmin = 5.2°
Absorption correction: numerical (SADABS; Sheldrick, 2008)	h = −10→10
Tmin = 0.638, Tmax = 0.861	k = −5→6
3854 measured reflections	l = −13→13

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.029	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.070	w = 1/[σ2(Fo2) + (0.0304P)2 + 0.27P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max < 0.001
906 reflections	Δρmax = 0.25 e Å−3
77 parameters	Δρmin = −0.17 e Å−3
0 restraints	Extinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0140 (13)

Experimental. crystal mounted on a Cryoloop using Paratone-N

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.

	x	y	z	Uiso*/Ueq
O1	0.11919 (10)	0.09994 (19)	0.84099 (8)	0.0276 (3)
C1	0.20439 (13)	0.4459 (2)	0.63057 (10)	0.0164 (3)
H1	0.1194	0.5695	0.5949	0.020*
O2	0.42464 (10)	0.29447 (16)	0.57144 (8)	0.0226 (3)
C2	0.13692 (14)	0.1810 (2)	0.63346 (11)	0.0190 (3)
H2A	0.0251	0.1641	0.5863	0.023*
H2B	0.2016	0.0472	0.6132	0.023*
O3	0.35444 (10)	0.69510 (15)	0.53889 (8)	0.0197 (3)
H3	0.4319 (19)	0.696 (3)	0.5052 (14)	0.030*
C3	0.16234 (13)	0.2142 (2)	0.76737 (11)	0.0187 (3)
C4	0.25515 (14)	0.4542 (2)	0.77165 (11)	0.0204 (3)
H4A	0.3698	0.4359	0.8096	0.024*
H4B	0.2126	0.5984	0.8053	0.024*
C5	0.33761 (13)	0.4681 (2)	0.57643 (10)	0.0158 (3)

	U11	U22	U33	U12	U13	U23
O1	0.0220 (5)	0.0380 (6)	0.0232 (5)	−0.0043 (4)	0.0075 (4)	0.0098 (4)
C1	0.0165 (6)	0.0169 (6)	0.0165 (6)	0.0006 (4)	0.0056 (4)	0.0008 (5)
O2	0.0221 (5)	0.0194 (5)	0.0304 (5)	0.0050 (4)	0.0140 (4)	0.0079 (4)
C2	0.0194 (6)	0.0187 (7)	0.0206 (6)	−0.0032 (5)	0.0085 (5)	−0.0026 (5)
O3	0.0222 (5)	0.0155 (5)	0.0254 (5)	0.0003 (3)	0.0132 (4)	0.0021 (3)
C3	0.0135 (6)	0.0229 (7)	0.0198 (6)	0.0018 (5)	0.0049 (4)	0.0033 (5)
C4	0.0208 (6)	0.0253 (7)	0.0162 (6)	−0.0041 (5)	0.0071 (5)	−0.0035 (5)
C5	0.0165 (6)	0.0168 (6)	0.0132 (5)	−0.0004 (5)	0.0028 (4)	0.0006 (4)

O1—C3	1.2024 (15)	C2—H2A	0.9900
C1—C5	1.4983 (16)	C2—H2B	0.9900
C1—C2	1.5458 (17)	O3—C5	1.3164 (15)
C1—C4	1.5701 (16)	O3—H3	0.885 (18)
C1—H1	1.0000	C3—C4	1.5217 (17)
O2—C5	1.2225 (15)	C4—H4A	0.9900
C2—C3	1.5171 (17)	C4—H4B	0.9900
C5—C1—C2	116.17 (10)	O1—C3—C2	133.43 (12)
C5—C1—C4	114.48 (9)	O1—C3—C4	133.61 (12)
C2—C1—C4	89.94 (9)	C2—C3—C4	92.88 (9)
C5—C1—H1	111.5	C3—C4—C1	87.33 (9)
C2—C1—H1	111.5	C3—C4—H4A	114.1
C4—C1—H1	111.5	C1—C4—H4A	114.1
C3—C2—C1	88.37 (9)	C3—C4—H4B	114.1
C3—C2—H2A	113.9	C1—C4—H4B	114.1
C1—C2—H2A	113.9	H4A—C4—H4B	111.3
C3—C2—H2B	113.9	O2—C5—O3	123.66 (11)
C1—C2—H2B	113.9	O2—C5—C1	123.18 (11)
H2A—C2—H2B	111.1	O3—C5—C1	113.12 (10)
C5—O3—H3	109.3 (10)
C5—C1—C2—C3	126.54 (10)	C5—C1—C4—C3	−128.00 (10)
C4—C1—C2—C3	9.07 (8)	C2—C1—C4—C3	−9.05 (8)
C1—C2—C3—O1	167.67 (14)	C2—C1—C5—O2	−24.15 (16)
C1—C2—C3—C4	−9.38 (9)	C4—C1—C5—O2	78.70 (14)
O1—C3—C4—C1	−167.80 (14)	C2—C1—C5—O3	158.11 (10)
C2—C3—C4—C1	9.24 (9)	C4—C1—C5—O3	−99.04 (12)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2i	0.885 (18)	1.756 (18)	2.6392 (12)	175.74 (15)
C1—H1···O1ii	1.00	2.45	3.1003 (15)	122

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O2i	0.885 (18)	1.756 (18)	2.6392 (12)	175.74 (15)
C1—H1⋯O1ii	1.00	2.45	3.1003 (15)	122

Symmetry codes: (i) ; (ii) .