Homo- and heteroleptic zinc aminophenolates as initiators for lactide polymerization

The reaction of ZnEt2 with one or two equivalents of aminophenolate ligand N-[methyl(2-hydroxy-3, 5-di-tert-butylphenyl)]-N-methyl-N-cyclohexylamine gives hetero- and homoleptic molecular compounds [(mu, eta(2)-L-2)ZnEt](2) and [Zn(eta(2)-L-2)(2)]. The later is most probably a mixture of diastereoisomers that in solution shows an interesting dynamic behaviour. Both complexes as well as the BnOH derivative of the latter, [(eta(2)-L-2)Zn(mu-BnO)](2), proved excellent initiators for lactide polymerization.