PPh3/DDQ as a neutral system for the facile preparation of diethyl α-bromo, α-iodo and α-azidophosphonates from diethyl α-hydroxyphosphonates

The mixture of triphenylphosphine (PPh3) and 2,3-dichloro-5,6-dicyanobenzquinone (DDQ) as a neutral system has been used for the preparation of various types of diethyl α-bromo, α-iodo and α-azidophosphonates from their corresponding diethyl α-hydroxyphosphonates in the presence of n-Bu4NBr, n-Bu4NI and NaN3 in good to high yields.