Chem. Pharm. Bull. 55(11) 1593—1596 (2007)

features, which are used in the field of bioactive materials as medicine or agricultural chemicals and functional materials as polymers or liquid crystals. Therefore, many people have actively investigated the synthesis and/or the reaction of fluorinated compounds, and there are a lot of reports about them. On the other hand, the formation of a quaternary carbon center has recently attracted great attention in synthetic organic chemistry. For example, the bioactive compounds such as carotenoids or steroids contain one or more quaternary carbon center(s) in their molecules, and their synthesis is an important subject of research. However, there are only a few reports on the formation of a quaternary carbon–carbon bond with a fluorinated substituent. Recently, we have reported the synthesis of a-trifluoromethylated ketones or a-fluoroalkylated ketones from a ,b-unsaturated ketones (1) by the reaction of trifluoromethyl iodide or a ,a-difluoro halogen compounds (2) in the presence of Et2Zn and RhCl(PPh3)3 (Chart 1). Herein, we would like to report the Pd-catalyzed allylation reaction of 3 for the formation of a quaternary carbon center that has a fluoroalkyl group (Chart 2).