O-Methyl-bis-O-(4-nitrophenyl)phosphite: a novel chemoselective O-phosphitylating reagent

A novel chemoselective O-phosphitylating reagent containing two aryloxy leaving groups at a P(III) center is developed for selective formation of P(III) esters from amino alcohols without the need to protect the amino group. The reagent proved to be highly convenient for the synthesis of dinucleotides, P(III)–F structures, and cyclic P(III) nucleotides.