Phosphorus-containing heterocycles from phosphorus(III) reagents and ortho-azidoaromatic compounds: synthesis of 2,2-di(dimethylamino)-1,3,2-benzoxazaphosphole and various 2,3-dihydro-1,3,2-benzoxazaphosph(V)oles

Abstract

o-Azidophenol reacts with methyl diphenylphosphinite to give the amino(oxy)phosphorane, 2-methoxy-2,2-diphenyl-2,3-dihydro-1,3,2-benzoxazaphosph(V)ole (1; 90%), which is also produced (55%) from o-aminophenol, the phosphinite, and N-chlorodi-isopropylamine; o-azidophenyl benzoate reacts with hexa-methylphosphorous triamide to give 2,2-di(dimethylamino)-1,3,2-benzoxazaphosphole (2; 76%) and NN-dimethylbenzamide.