Cross-coupling of (Z)-1,2-bis(ethylseleno)ethene with the Grignard reagents

The nickel-catalyzed cross-coupling of (Z)-1,2-bis(ethylseleno)ethene with the alkyl magnesium bromides proceeds with substitution of both ethylseleno groups to afford symmetrical alkenes, (Z)-RCHCHR, in high yield with complete retention of configuration. In the case of phenyl magnesium bromide the monoarylation occurs to form (Z)-2-ethylseleno styrene, EtSeCHCHPh.