PPh3/DDQ as a neutral system for the facile preparation of diethyl α-bromo, α-iodo and α-azidophosphonates from diethyl α-hydroxyphosphonates
作者:Habib Firouzabadi、Nasser Iranpoor、Sara Sobhani
DOI:10.1016/j.tet.2003.10.058
日期:2004.1
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.
Controlled monohalogenation of phosphonates: A new route to pure α-monohalogenated diethyl benzylphosphonates
作者:Bogdan Iorga、Frédéric Eymery、Philippe Savignac
DOI:10.1016/s0040-4020(99)00037-x
日期:1999.2
Starting from diethyl benzylphosphonates, a wide variety of diethyl α-monofluoro, chloro, bromo and iodobenzylphosphonates have been obtained in pure form by a one-pot procedure. This high yielding method implies the intermediate protection of the benzyl anion with TMSCl followed by halogenation with an electrophilic halogenating reagent.