Crystal structures and hydrogen bonding schemes in four benzamide derivatives (2-hydroxy-benzamide, 2-hydroxy-thiobenzamide, 2-hydroxy-N,N-dimethyl-benzamide, and 2-Hydroxy-N,N-dimethyl-thiobenzamide)

摘要

2-Hydroxy-benzamide, C7H7NO2; monoclinic; I2/a-C2h6;a=12.901 (2),b=4.982 (1),c=20.987 (3) Å; β=91.50 (2)°;Z=8. 2-Hydroxy-thiobenzamide, C7H7NOS; monoclinic; P21/n-C2h5;a=13.508 (5),b=6.780 (2),c=15.878 (6) Å; β=93.74 (5)°;Z=8. 2-Hydroxy-N,N-dimethyl-benzamide, C9H11NO2; orthorhombic; Pbca-D2h15;a=11.752 (2),b=16.680 (3),c=9.079 (2) Å;Z=8. 2-Hydroxy-N,N-dimethyl-thiobenzamide, C9H11NOS; monoclinic; P21/c-C2h5;a=6.983 (1),b=11.652 (3),c=11.704 (3) Å; β=100.02 (2)°;Z=4. The crystal structures of these four compounds were determined (respectively refined: 2-hydroxy-benzamide) by single crystal X-ray data. The refinements of the structure parameters by least squares methods yielded in all casesR<0.056. The hydrogen atoms were located by means of difference Fourier summations. The O-H ... O distances are 2.513 (1) Å in 2-hydroxy-benzamide (intramolecular) and 2.625 (1) Å in 2-hydroxy-N,N-dimethyl-benzamide (intermolecular). The two O-H ... S distances in 2-hydroxy-thiobenzamide are 2.904 (2) Å and 2.918 (2) Å (intramolecular, two molecules in the asymmetric unit) and 3.228 (2) Å in 2-hydroxy-N,N-dimethyl-thiobenzamide (intermolecular). Clear N-H ... O hydrogen bonds with 2.926 (1) Å and 3.006 (1) Å occur only in the structure of 2-hydroxy-benzamide