Nitrodibromoacetonitrile: an agent for bromination and for the formation of adducts formally derived from cyanonitrocarbene

Abstract

The reactions of nitrodibromoacetonitrile (NDBA) with alkenes, aromatic compounds, amines, and sulphides have been studied. Products were formally derived from bromine or nitrocyanocarbene except for bis(2-bromocyclohexyl)nitroacetonitrile (13), an adduct (2 : 1) obtained from cyclohexene and NDBA. 2,3-Dimethylbut-2-ene was converted into 3-cyano-4,4,5,5-tetramethyl-4,5-dihydroisoxazole 2-oxide (15) and 2,3-dibromo-2,3-dimethylbutane (16). meso-1,2-Dibromo-1,2-diphenylethane was obtained from trans-stilbene. In a reaction catalysed by copper, benzene and NDBA gave benzoyl cyanide. From anthracene, phenol, and cupric acetylacetonate, 9,10-dibromoanthracene, 4-bromophenol, and cupric bromoacetylacetonate were obtained respectively. Dimethyl sulphide, tetrahydrothiophene, and triethylamine afforded the corresponding sulphonium-(30) and (31) and ammonium cyanomethylide-(33) derivatives and, with the latter, co-formation of triethylammonium bromide. Rationales for the reactions are discussed.