Synthesis and catalytic activity of three-coordinate zinc cations

Reaction between DADZnR(2) and either B(C6F5)(3) or ZnR2 and [DADH][B(C6F5)(4)] affords three-coordinate alkyl and amide zinc cations which are active for the ring opening polymerisation of epoxides and epsilon-caprolactone [DAD = (MeC =NC6H3Pr2i-2,6)(2)].