D. Darensbourg, A. Moncada
Jun 30, 2010
Citations
0
Influential Citations
69
Citations
Journal
Macromolecules
Abstract
The (salen)CrIIICl complex 1, (1,2-cyclohexanediamino-N,N′-bis(3,5-ditert-butylsalicylidene)chromium(III) chloride), in the presence of n-Bu4NX (X = Br, I, Cl, N3, NCO) as cocatalyst has been shown to be an effective catalytic system for the coupling of oxetane and CO2 providing the corresponding aliphatic polycarbonate with small quantities of ether linkages at 110 °C. The selectivity of the oxetane and CO2 coupling process has been effectively tuned for the formation of polycarbonate produced directly from the homopolymerization of preformed trimethylene carbonate (TMC), in the presence of complex 1 along with n-Bu4NBr as cocatalyst, at temperatures lower than 80 °C. Notably, under these conditions the amount of carbonate linkages obtained was remarkably high (>99%). An investigation of the initial catalytic species involved in the coupling reaction was performed by ESI mass spectral analysis, revealing a Schlenk (ligand redistribution) equilibrium of the three possible anions formed after treatment of ...