To provide a method for readily synthesizing a fluorine-containing connecting group between cyclic hydrocarbons such as aryl groups, perfluoroaryl groups, cyclohexyl groups, etc., useful in a liquid-crystal.

The method for synthesizing a fluorine-containing connecting group represented by formula -(V)mCF2CFY(W)n- between A and B by any one of six processes (only one is described). (1) A Grignard reagent AMgX and a fluorinated olefin CF2=CFY are subjected to addition reaction, a formed carbanion is reacted with a halogen compound BX' or an aryl ether compound BOC6H4Z to give an A-CF2CFY-B (A and B are each an aryl group, a perfluoroaryl group or a cyclohexyl group; X is Cl, Br or I; X' is Br or I; Y is F, Cl, Br, Rf or ORf: Rf is a 1-3C perfluoroalkyl group; Z is NO2, CF3 or F; V is O, S or SO2; W is CF2, CF2O, CFCl, CCl2, CO or COO: m and n are each 0 or 1).