The fluoro-sulfur containing olefins cis-C6F5SCH2CH=CHCH2SC6F5 (1), cis-p-C
6HF4SCH2CH=CHCH2S-p-C6HF4 (2) and cis-p-C6H4FSCH2CH=CHCH2S-p-C6H4F (3) as w
ell cis-C6H5SCH2CH=CHCH2SC6H5 (4) have been prepared by treatment of cis-Cl
CH2CH=CHCH2Cl with the corresponding Pb(SR)(2) or NaSC6H5.