β-(keto or sulfonyl)esters from reaction of silylketene acetal and acyl or sulfonyl compound

Claim 1

Process for preparing beta-ketoesters or beta-sulfonylesters comprising contacting and reacting a silylketene acetal with an acyl or sulfonyl compound in the presence of a catalyst which is a source of, (1) an anion selected from the group comprising fluoride, difluorotrimethylsilicate, bifluoride, cyanide and azide ions; or (2) an oxyanion which forms a conjugate acid having a pKa measured in dimethylsulfoxide at 25° C., of about 5 to about 24, the silylketene acetal being of the formula ##STR9## wherein: each Q, independently, is selected from --R 1 , --OR 1 , --N(R 1 ) 2 and --SR 1 ; each R 1 , independently, is a hydrocarbyl or substituted hydrocarbyl radical; R 3 is H, hydrocarbyl or substituted hydrocarbyl; each of R 2 and R 4 , independently, is a hydrocarbyl, substituted hydrocarbyl, or a polymeric radical, the acyl or sulfonyl compound being selected from the group consisting of [XC(O)] n R 5 and [YS(O) 2 ] n R 5 wherein: X is a silicon activating group; Y is --F or --OAr; Ar is aryl or substituted aryl; R 5 is a hydrocarbyl, substituted hydrocarbyl or polymeric radical, of valence n, wherein the carbon adjacent to the C(O) or S(O) 2 is not part of a carbon-carbon double or triple bond; and n is an integer of at least 1.