Four substituted benzohydrazides: hydrogen-bonded structures in one, two and three dimensions

The molecules of 2,6-dichloro-benzohydrazide, C7H6Cl2N2O, are linked into simple chains by a single N-H center dot center dot center dot O hydrogen bond, while in the isomeric compound 2,4-dichloro-benzo-hydrazide, the molecules are linked by N-H center dot center dot center dot N and N-H center dot center dot center dot O hydrogen bonds into complex sheets comprising an inner polar layer sandwiched between two non-polar layers. In 4-amino-2-chloro-benzohydrazide monohydrate, C7H8ClN3O center dot H2O, the components are linked into a three-dimensional framework by a combination of O-H center dot center dot center dot O, O-H center dot center dot center dot N, N-H center dot center dot center dot N and N-H center dot center dot center dot O hydrogen bonds, and in 2-nitro-benzohydrazide, C7H7N3O3, a three-dimensional framework is formed by a combination of N-H center dot center dot center dot N and N-H center dot center dot center dot O hydrogen bonds.