PHOSPHORIC-CARBOXYLIC ANHYDRIDES - NEW SYNTHETIC PROCEDURES AND REACTIONS WITH NUCLEOPHILES - REEXAMINATION OF THE REACTION OF SE-ALKYL-PHOSPHOROSELENOATES WITH ALCOHOLS AND MERCURIC TRIFLUOROACETATE

Phosphorus trimethylsilyl esters KR'P(O)OSiMe(3) react smoothly with c arboxylic anhydrides to give phosphoric-carboxylic anhydrides RR'P(O)- O-COR'' in excellent yield. A similar reaction proceeds between stanny l esters RR'P(O)OSnMe(3) and carboxylic anhydrides. We also have found that the anhydrides RR'P(O)-O-COCF3 are formed in almost quantitative yield when the phosphorus acid halides RR'P(O)X (X = Cl, Br, I) are a llowed to react with trifluoroacetic anhydride in the presence of N-me thylimidazole. We were able to confirm again that acyclic phosphoric-c arboxylic anhydrides exhibit acetylating properties towards amines and alcohols. Our findings contradict with those of Wozniak, Krzyzanowska and Stec [6] relating to the reaction of Se-alkylphosphoro-selenoates RR'P(O)SBR'' with mercuric trirluoroacetate Hg(OCOCF3)(2). Our interp retation of this reaction differs entirely From those presented by the above mentioned authors.