Syntheses and crystal structures of benzyl N '-[( E )-2-hydroxybenzylidene]hydrazinecarboxylate and benzyl N '-[( E )-5-bromo-2-hydroxybenzylidene]hydrazinecarboxylate.

Benzyl N '-[( E )-2-hydroxybenzylidene]hydrazinecarboxylate, C 15 H 14 N 2 O 3 ( I ) and benzyl N '-[( E )-5-bromo-2-hydroxybenzylidene]hydrazinecarboxylate ( II ), C 15 H 13 BrN 2 O 3 , have been synthesized by the reaction of either 2-hy-droxy-benzaldehyde or 5-bromo-2-hy-droxy-benzaldehyde with benzyl carbazate, respectively. Both the compounds crystallize in the monoclinic crystal system with space groups Pn ( Z ' = 1, I ) and P 2 1 / c ( Z ' = 2, II ). Mol-ecular conformations in each structure are similar, and both structures feature strong intra-molecular O-H⋯N hydrogen bonds, which form S (6) ring motifs. There are also strong N-H⋯O and weak C-H⋯O hydrogen bonds in both structures, but their modes of packing within their respective crystals are markedly different. Some comparisons are made with the structures of a few related compounds.