Dialkyl phosphates esterification

Esterification of dialkyl phosphates is carried out with diethyl azodicarboxylate and triphenylphosphine (equation 46). This condensation is applicable to phosphorylation of pyrimidine nucleosides. The trichloromethanephosphonic acid derivative (69 equation 47) serves as a phosphorylating agent of ribonucleosides, affording the 2 - and 3 -monophosphates. ° Ethyl vinyl ether assisted the dimeric condensation of diethyl hydrogen phosphate giving tetraethyl pyrophosphate (equation 48). ... 

Phosphate esters are prepared by the partial esterification of fatty alcohol with phosphorous oxychloride followed by hydrolysis (20). This method yields a product that is a mixture of monoalkyl, dialkyl, and trialkyl phosphates. 

The phospht lation of alditols, oligosaccharides, and glycoproteins by use of sodium phosphate in anhydrous media has been described, and a papct on the direct esterification of a dialkyl phoqthate with organic halides in the presence of silver oxide included a number of carbohydrate examples, such as the formation of peracetylated -D-galactosyl phosphate from a-acetobromogalactose. Chl(MO-W, -diisopropylaminoalkoxyphoq)hines [ROP(Cl)N(i-Pr)2J in P3mdine... 

---