The study of the Julia–Kocienski reaction between fluorinated arylsulfone and ketones is described. The corresponding fluoroalkenes were isolated in moderate to good yields from β- and δ-substituted cyclic ketones. From acyclic ketones and α-substituted cyclic ketones a decarbethoxylation reaction of the sulfonylesters occurred. This decarbethoxylation reaction opened a new route for the preparation
The enantioselective Horner-Wadsworth-Emmons reaction of 2-fluoro-2-dietliylphosphonoacetates with sigma-symmetric prochiral 2-substituted-1,3-dioxan-5-ones and 4-substituted-cyclohexanones was investigated by employing Sn(OSO2CF3)(2) and N-ethylpiperidine in the presence of an external chiral ligand, (S)-(-)-1-methyl-2-(1-piperidinomethyl)pyrrolidine. A chiral alpha-fluoro-alpha,beta-unsaturated ester was obtained in up to 80% ce. (C) 2002 Elsevier Science Ltd. All rights reserved.