NICKEL(II) CATALYZED SUBSTITUTION OF HALOGENS IN 1-HALO-1-CHALCOGENE ALKENES BY CHALCOGENATE ANIONS

Bis(bipyridine)nickel (II) bromide catalyzes the substitution of chlor ine, bromine and iodine in 1-halo-1-chalcogene alkenes [RCH=CX(YR1), R =C6H5, n-C4H9; R-1=CH3, C6H5; X=Cl, Br, I; Y=S, Se] by phenylselenolat e and phenyltellurolate anions leading to the S-Se, Se-Te and Se-Se as ymmetrically substituted ketene chalcogeneacetals [RCH=C(YR1)(YC6H5)-C -1] under mild conditions (30-70 degrees C, 1 atm) and in good yields (80-95%) within a short reaction time (10-60 min). The following compo unds were prepared: C6H5CH=C(SeCH3)SeC6H5, C6H5CH=C(SCH3)SeC6H5, n-C4H 9CH =C(SeCH3)SeC6H5, n-C4H9CH=C(SCH3)SeC6H5, n-C4H9CH=C(SC6H5)SeC6H5, n-C6H5 CH=C(SeCH3) TeC6H5.