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-hy­droxy­benzaldehyde or 5-bromo-2-hy­droxy­benzaldehyde with benzyl carbazate, respectively. Both the compounds crystallize in the monoclinic crystal system with space groups Pn (Z′ = 1, I) and P2(1)/c (Z′ = 2, II). Mol­ecular conformations in each structure are similar, and both structures feature strong intra­molecular 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.