Method for Producing Optically Active Fluorinated Oxetane

Disclosed is a method of producing an optically active fluorinated oxetane, which can be an important pharmaceutical or agricultural intermediate, by reaction of a fluorinated α-keto ester with an acyl alkenyl ether in the presence of a transition metal complex with an optically active ligand. This method utilizes a catalytic asymmetric synthesis process and does not require a stoichiometric amount of chiral source. It is thus possible to dramatically reduce the amount of use of the asymmetric catalyst especially when the reaction is performed at a high concentration of substrate (with the use of a small amount of reaction solvent) or in the absence of a reaction solvent (under neat conditions). Further, the target optically active fluorinated oxetane can be obtained with high yield and with very high optical purity. The product contains almost no difficult-to-separate impurity and shows high chemical purity.