Crystal structure of 4-formylpyridine semicarbazone hemihydrate

Abstract

The molecule of the title compound C7H8N4O·0.5H2O, alternatively called (E)-1-(pyridin-4-ylmethylene) semicarb-azide hemihydrate, is in the E conformation and is almost planar; the r.m.s. deviation of the positions of the atoms of the pyridine ring from the best-fit plane is 0.0039 Å. The C, N and O atoms of the rest of the molecule sits close on this plane with a largest deviation of 0.115 (4) Å for the O atom of the semicarbazone moiety. There is an intramolecular N - H⋯N hydrogen bond. In the crystal, molecules are linked into an infinite three-dimensional network by classical N - H⋯Os (s = semicarbazone) and Ow - H⋯N (w = water) hydrogen bonds.