Crystal structures of N-(4-methyl phenyl)-2,2,2-trichloroacetamide, N-(2,3-dimethyl phenyl)-2,2,2-trichloroacetamide and N-(2-nitro phenyl)-2,2,2-trichloroacetamide

The crystal structures of N-(4-methyl phenyl)-2,2,2-trichloroacetamide, C9H8Cl3NO (1), N-(2,3-dimethyl phenyl)-2,2,2-trichloroacetamide, C10H10C13NO (2) and N-(2-nitro phenyl)-2,2,2-trichloroacetamide, C8H5Cl3N2O3 (3) have been determined at room temperature (1): P2(1)/c, a = 9.658(3) Angstrom, b = 20.243(5) Angstrom, c = 11.441(3) Angstrom, beta = Z = 8, (2): Pna2(1), a = 19.233(5) Angstrom, b = 5.970(2) Angstrom, c = 20.805(5) Angstrom, Z = 8, (3): P (1) over bar, a = 6.809(3) Angstrom, b = 12.717(6) Angstrom, c = 13.240(6) Angstrom, a = 98.67(2)degrees, beta = 96.14(2)degrees, gamma = 101.47(2)degrees. The phenyl rings as well as the acetamide group are planar. Their orientation suggests very little strain and hence little pi-bonding. For (1) substitution by a methyl group at C(4) position in the phenyl ring results in a marked deviation in the C(3)-C(4)-C(5) angle from 120 degrees.