Regiospecific Cp*Ru+ mediated codimerization of conjugated dienes with non-conjugated 1,5-dienes and its application to catalytic cooligomerization
When Cp*RuCl(η4-butadiene) (1; where Cp* = η5-C5Me5) was treated with an excess of 1,5-hexadiene in the presence of silver trifluoromethanesulfonate (AgOTf) at or below ambient temperature, a 2-(3'-butenyl)-1,5-hexadiene complex of cationic ruthenium was obtained by regiospecific C4 homologation at the internal carbon atom of the non-conjugated diene.This stoichiometric C-C bonding was extended to the catalytic codimerization and stepwise oligomerization of butadiene with 1,5-hexadiene or 1-hexene.