REDUCTION OF NITRO-COMPOUNDS AND NITROSO-COMPOUNDS BY TERVALENT PHOSPHORUS REAGENTS .V. REDUCTION OF ALKYL-NITROBENZENES AND METHOXY-NITROBENZENES, AND NITROBENZENE, BY TRIALKYL PHOSPHITES

Reactions of triethyl- and trimethyl-phosphites with o-, m-, and p-nitrotoluene, o- and p-ethylnitrobenzene, o- and p-nitroanisole, and nitrobenzene give the corresponding dialkyl N-arylphosphoramidates and dialkyl N-alkyl-N-arylphosphoramidates, and, in some cases, trialkyl N-arylphosphorimidates, the probable precursors of the above amidates. In some cases low (≤S18%) yields of dialkyl alkyl-3H-azepin-7-ylphosphonates are formed, indicating the intermediacy of nitrenoid species. Reaction of triethyl phosphite with p-ethyl-, p-methyl-, and p-methoxy-nitrobenzenes, and of trimethyl phosphite with o-nitroanisole and p-nitrotoluene give low yields of the corresponding dialkyl arylphosphonates, representing the first recorded instances of displacement of a simple aromatic nitro-group unactivated by either electronic influences or special steric factors.