To obtain the subject new compound useful as an intermediate compound for medicines/agrochemicals.

This new compound is shown by formula I (R1 is a lower alkyl, a lower alkoxy, a halogen or the like; R2 and R3 are each H or a lower alkyl; *denotes an asymmetric carbon atom), e.g. 4-phenyl-2-allyloxy-1-chloro-1,1- difluorobutane. The compound of formula I is obtained by reaction of an optically active chlorodifluoroethyl allyl ether of formula II with pref. 0.05-0.5 molar times, based on the allyl ether of formula II, of tributyltin hydride in the presence of 0.05-0.2 molar times of a radical reaction initiator (e.g. azoisobutyronitrile) in a solvent of 0.5-20 wt. times (e.g. benzene, toluene) pref. at 50-140°C. By the way, the compound of formula II is prepared by reaction of an optically active 2-hydroxy-1-chloro-1,1-difluoroethyl compound of formula III with an allyl halide of formula IV (X is a halogen).