(−)-cis-1-Acetyl-3-ethynyl-2,2-dimethyl­cyclo­butane

The title compound, C₁₀H₁₄O, adopts a conformation typical of cis-1,3-disubstituted cyclo­butanes, with the ring flexed out of planarity so that the substituents are maximally separated. The two inter­molecular C—H...O=C close contacts found include one involving the acetyl­enic H atom.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.035
• wR factor = 0.095
• Data-to-parameter ratio = 9.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT710_ALERT_4_C Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         21
            C4  -C3  -C9  -C10    49.00  6.00   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_C Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         22
            C2  -C3  -C9  -C10   156.00  6.00   1.555   1.555   1.555   1.555

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           68.04
           From the CIF: _reflns_number_total               1001
           Count of symmetry unique reflns         1004
           Completeness (_total/calc)             99.70%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C1     = .          R
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C3     = .          R

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   3 ALERT level G = General alerts; check

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

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Computing details

Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2004); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

(-)-cis-1-Acetyl-3-ethynyl-2,2-dimethylcyclobutane

Crystal data

C10H14O	Dx = 1.073 Mg m^−3
Mr = 150.21	Melting point: 316 K
Orthorhombic, P212121	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: P 2ac 2ab	Cell parameters from 5748 reflections
a = 6.5329 (2) Å	θ = 3.0–68.0°
b = 11.5432 (5) Å	µ = 0.52 mm^−1
c = 12.3324 (5) Å	T = 100 K
V = 929.99 (6) Å^3	Oblong prism, colourless
Z = 4	0.21 × 0.07 × 0.07 mm
F(000) = 328

Data collection

Bruker SMART CCD APEXII area-detector diffractometer	1001 independent reflections
Radiation source: fine-focus sealed tube	916 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
φ and ω scans	θmax = 68.0°, θmin = 5.3°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −7→7
Tmin = 0.898, Tmax = 0.963	k = −12→13
5748 measured reflections	l = −14→14

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.095	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0522P)^2 + 0.1958P] where P = (Fo^2 + 2Fc^2)/3
1001 reflections	(Δ/σ)max < 0.001
104 parameters	Δρmax = 0.19 e Å^−3
0 restraints	Δρmin = −0.12 e Å^−3

Special details

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	1.0413 (3)	0.19304 (13)	0.59997 (12)	0.0421 (4)
C1	0.9376 (3)	0.29439 (18)	0.75829 (15)	0.0294 (5)
H1	1.0011	0.3675	0.7859	0.035*
C2	0.7072 (3)	0.28551 (18)	0.79641 (15)	0.0277 (5)
C3	0.7904 (3)	0.21663 (19)	0.89641 (16)	0.0322 (5)
H3	0.8199	0.2721	0.9567	0.039*
C4	0.9901 (3)	0.1928 (2)	0.83300 (17)	0.0346 (5)
H4A	1.1161	0.2047	0.8762	0.041*
H4B	0.9924	0.1168	0.7959	0.041*
C5	0.9744 (3)	0.28201 (18)	0.63815 (16)	0.0305 (5)
C6	0.9231 (4)	0.3838 (2)	0.56894 (16)	0.0362 (5)
H6A	1.0484	0.4270	0.5523	0.054*
H6B	0.8273	0.4343	0.6077	0.054*
H6C	0.8600	0.3571	0.5013	0.054*
C7	0.5784 (3)	0.21029 (19)	0.72082 (16)	0.0340 (5)
H7A	0.4474	0.1924	0.7557	0.051*
H7B	0.6518	0.1381	0.7053	0.051*
H7C	0.5535	0.2521	0.6529	0.051*
C8	0.5993 (4)	0.39884 (19)	0.82303 (19)	0.0421 (6)
H8A	0.5651	0.4394	0.7556	0.063*
H8B	0.6898	0.4476	0.8670	0.063*
H8C	0.4736	0.3826	0.8636	0.063*
C9	0.6751 (3)	0.1182 (2)	0.93933 (16)	0.0331 (5)
C10	0.5874 (4)	0.03687 (19)	0.97558 (17)	0.0358 (5)
H10	0.5172	−0.0282	1.0046	0.043*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0481 (10)	0.0373 (9)	0.0408 (8)	0.0008 (8)	0.0104 (8)	−0.0090 (7)
C1	0.0279 (10)	0.0295 (10)	0.0307 (9)	−0.0030 (10)	0.0005 (9)	−0.0031 (8)
C2	0.0277 (10)	0.0274 (10)	0.0281 (10)	0.0009 (9)	0.0029 (9)	−0.0003 (8)
C3	0.0311 (11)	0.0348 (11)	0.0309 (10)	−0.0006 (10)	0.0005 (9)	−0.0014 (9)
C4	0.0257 (10)	0.0434 (12)	0.0346 (10)	−0.0012 (10)	−0.0015 (9)	0.0053 (9)
C5	0.0258 (10)	0.0326 (11)	0.0333 (10)	−0.0065 (9)	0.0029 (8)	−0.0045 (8)
C6	0.0364 (11)	0.0392 (12)	0.0331 (10)	−0.0070 (11)	0.0024 (10)	−0.0016 (9)
C7	0.0255 (9)	0.0413 (12)	0.0353 (10)	−0.0014 (11)	−0.0014 (9)	0.0031 (10)
C8	0.0474 (13)	0.0362 (12)	0.0426 (12)	0.0105 (11)	0.0125 (12)	−0.0004 (10)
C9	0.0292 (10)	0.0385 (12)	0.0316 (10)	0.0053 (11)	0.0026 (9)	−0.0007 (9)
C10	0.0322 (11)	0.0368 (12)	0.0386 (11)	0.0006 (10)	0.0034 (10)	0.0069 (9)

Geometric parameters (Å, º)

O1—C5	1.211 (2)	C5—C6	1.490 (3)
C1—C5	1.508 (3)	C6—H6A	0.9800
C1—C4	1.530 (3)	C6—H6B	0.9800
C1—C2	1.581 (3)	C6—H6C	0.9800
C1—H1	1.0000	C7—H7A	0.9800
C2—C8	1.522 (3)	C7—H7B	0.9800
C2—C7	1.527 (3)	C7—H7C	0.9800
C2—C3	1.565 (3)	C8—H8A	0.9800
C3—C9	1.462 (3)	C8—H8B	0.9800
C3—C4	1.546 (3)	C8—H8C	0.9800
C3—H3	1.0000	C9—C10	1.187 (3)
C4—H4A	0.9900	C10—H10	0.9500
C4—H4B	0.9900
C5—C1—C4	118.90 (18)	O1—C5—C6	121.79 (18)
C5—C1—C2	115.96 (16)	O1—C5—C1	121.32 (19)
C4—C1—C2	89.12 (15)	C6—C5—C1	116.89 (18)
C5—C1—H1	110.4	C5—C6—H6A	109.5
C4—C1—H1	110.4	C5—C6—H6B	109.5
C2—C1—H1	110.4	H6A—C6—H6B	109.5
C8—C2—C7	111.44 (18)	C5—C6—H6C	109.5
C8—C2—C3	115.32 (17)	H6A—C6—H6C	109.5
C7—C2—C3	112.57 (17)	H6B—C6—H6C	109.5
C8—C2—C1	116.71 (18)	C2—C7—H7A	109.5
C7—C2—C1	112.34 (16)	C2—C7—H7B	109.5
C3—C2—C1	86.35 (15)	H7A—C7—H7B	109.5
C9—C3—C4	118.66 (19)	C2—C7—H7C	109.5
C9—C3—C2	120.06 (18)	H7A—C7—H7C	109.5
C4—C3—C2	89.15 (15)	H7B—C7—H7C	109.5
C9—C3—H3	109.1	C2—C8—H8A	109.5
C4—C3—H3	109.1	C2—C8—H8B	109.5
C2—C3—H3	109.1	H8A—C8—H8B	109.5
C1—C4—C3	88.80 (16)	C2—C8—H8C	109.5
C1—C4—H4A	113.8	H8A—C8—H8C	109.5
C3—C4—H4A	113.8	H8B—C8—H8C	109.5
C1—C4—H4B	113.8	C10—C9—C3	177.8 (2)
C3—C4—H4B	113.8	C9—C10—H10	180.0
H4A—C4—H4B	111.1
C5—C1—C2—C8	−102.2 (2)	C1—C2—C3—C4	−18.94 (16)
C4—C1—C2—C8	135.74 (19)	C5—C1—C4—C3	−138.80 (19)
C5—C1—C2—C7	28.2 (3)	C2—C1—C4—C3	−19.35 (15)
C4—C1—C2—C7	−93.79 (18)	C9—C3—C4—C1	143.80 (19)
C5—C1—C2—C3	141.16 (18)	C2—C3—C4—C1	19.55 (16)
C4—C1—C2—C3	19.14 (15)	C4—C1—C5—O1	1.1 (3)
C8—C2—C3—C9	100.1 (2)	C2—C1—C5—O1	−103.3 (2)
C7—C2—C3—C9	−29.3 (3)	C4—C1—C5—C6	−179.31 (18)
C1—C2—C3—C9	−142.01 (19)	C2—C1—C5—C6	76.3 (2)
C8—C2—C3—C4	−136.85 (18)	C4—C3—C9—C10	49 (6)
C7—C2—C3—C4	93.76 (19)	C2—C3—C9—C10	156 (6)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10···O1^i	0.95	2.27	3.178 (3)	160
C6—H6C···O1^ii	0.98	2.50	3.369 (3)	148

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