R. A. Olofson and J. Cuomo, Tetrahedron Lett., 21, 819 (1980) disclose fluoride ion catalyzed O-acylation of silyl enol ethers with compounds of the type RXC(O)F where X is O, NR' or a single bond, R is a cyclic or acyclic aliphatic radical and R' is methyl or, together with R, morpholino.