Homogeneous hydrogenation of the –NN–, –CHN–, and –NO2 groupings

Abstract

Using the previously described (py)₃RhCl₃–NaBH₄ catalyst in dimethylformamide with hydrogen, azobenzene is reduced to hydrazobenzene and slowly to aniline, benzalaniline gives benzylaniline, and nitrobenzene is reduced to aniline; pyridine and quinoline are hydrogenated to give piperidine and 1,2,3,4-tetrahydroquinoline respectively.