ShimizuShozo, KekkaShinji, KashinoSetsuo
Jul 1, 1974
Citations
1
Influential Citations
17
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
Crotonic acid crystallizes in the monoclinic space group C2/c, with a=15.30(3), b=4.06(1), c=16.18(2) A, β=107.4(1)° and Z=8; crotonamide in the monoclinic space group P21/a, with a=9.71(2), b=6.90(2), c=7.75(1) A, β=104.0(4)° and Z=4. The structures have been solved by the Patterson method and refined by the block-diagonal least-squares method. The final R values are 0.090 for 337 observed reflections for crotonic acid, and 0.088 for 525 observed ones for crotonamide. The configuration of the molecules of crotonic acid and crotonamide is approximately planar and of trans-type regarding the C=C bond. Every two centrosymmetrically related molecules form a dimer through hydrogen bonds of 2.645 A (OH···O) for crotonic acid and 2.963 A (NH···O) for crotonamide. In the crystals of crotonamide additional NH···O hydrogen bonds (2.862 A) link the neighboring molecules related by the a-glide plane to form a sheet parallel to (001) plane. Distances between the C=C bonds of the nearest neighbors are 3.86 A for croto...