Reaction of Ph₂C(X)(CO₂H) (X = OH, NH₂) with [VO(OR)₃] (R = Et, nPr): structure, magnetic susceptibility and ROP capability

Reaction of [VO(OR)(3)] (R = Et, nPr) with 2,2'-diphenylglycine afforded the alkoxide-bridged dimers {[VO(OR)(mu-OR)][Ph2C(NH2)(CO2)]}2, whereas use of benzilic acid, in the presence of alkali metals, afforded 16-membered metallocycles {V-8(O)(4)M(OR)(8)[Ph2C(OH)(CO2)](12)} (M = <1 Na, K). For the ring systems, magnetic susceptibility data is consistent with mixed-valence vanadium with an average oxidation state of 3.5. The dimer and ring systems are capable of the ring opening polymerisation (ROP) of epsilon-caprolactone under N-2, air, or as melts affording mostly low to medium molecular weight cyclic and linear products.