Enolphosphate phosphonates

Enolphosphate phosphonates derived from perfluoroalkanoylphosphonates have a number of synthetic uses. Reactions of such compounds with nucleophiles such as amines or alcohols in the presence of catalytic amounts of tetrabutylammonium fluoride (tbaf) gave a,j5-unsaturated perfluorocarboxylic acid derivatives, presumably via a ketene type intermediate (equation 94) When a primary amine was employed as the nucleophile a,j -unsaturated amides were formed, which could be converted into fluorinated pyrimidi-nones by treatment with urea. On the other hand, butylcopper(I) reagent reduces such... 

Machleidt, H., and Strehlke, G.U., Rearrangement between phosphonate and enolphosphate ester, Angew. Chem., 76, 494, 1964. 

An alternative to the Arbuzov route to P-keto phosphonates (40), alkylation of diethyl phosphorochloridite (41) with enolates followed by air-oxidation of the phosphonite, has been evaluated. Although some enolphosphate was formed, the ratios of P-C to P-O products were better than 12.5 1 under optimized conditions, and the products were easy to purify. The reaction is also useful for preparation of a-phosphono esters (42). A full paper has appeared on a new reagent (43) for the determination of optical purities of chiral alcohols or thiols. It is superior to previous reagents because of the large chemical shift difference between the diastereomeric products (44). 

Treatment of a-chloroepoxides with trialkyl phosphites leads to /8-keto-phosphonates free from enolphosphate contamination. 

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