In search of an efficient method to prepare cholinephosphate headgroups in phospholipids under mild conditions (where the diacylglycerol moiety is not subject to oxidation), a method was developed For phosphorylation using a trialkyl phosphite and I,. The active intermediate is a phosphoryl iodide formed by oxidation of the phosphite with I-2. 2-Bromoethanol, dimethyl chlorophosphite, and an alcohol (diglyceride) are converted to a phosphate triester in a one-pot reaction with high yield. In the second reaction, the phosphate triester is demethylated, and the ethyl bromide group is converted to choline by treatment with aqueous trimethylamine. This procedure is applied to the synthesis of hexadecylphosphocholine, and 1,2-didecanoyl-1 -deoxy-1-thio-sn-glyceryo-3-phosphocholine. (C) 2001 Published by Elsevier Science Ireland Ltd.