in tetrahydrofuran dropwise addn. of soln. of i-butylMgCl (68mmol) in THF (80ml) to suspension of 2CH3SCH2HgCl*HgCL2 (16.7mmol) in THF (50ml), stirring, -30°C; slowly warming up to room temp.; 2h, stirring; hydrolysis of excess Grignard compd. at -30°C;; addn. of HCl (2percent, 20ml), addn. of ether (50ml); removal of organic phase, washing of organic phase with water, drying over Na2SO4; removal of solvent; fractionating of residue in vac.; 13C-NMR;;