Reduction of nitro- and nitroso-compounds by tervalent phosphorus reagents. Part VI. An n.m.r. Spectroscopic investigation of 3H-azepines formed in such reactions

Abstract

N.m.r. spectroscopic evidence is presented to show that reductions of certain aromatic nitro-compounds by tervalent phosphorus reagents, described in the two preceding papers, give, among other products, derivatives of 3H-azepine. Thus, 2-nitrobiphenyl, o-nitrotoluene, or nitrobenzene with diethyl methylphosphonite in the presence of diethylamine gave 3-phenyl- or 3-methyl-2-diethylamino-3H-azepine, or 2-diethylamino-3H-azepine respectively, while various aromatic nitro-compounds with trialkyl phosphites gave substituted dialkyl 3H-azepin-7-ylphosphonates.