Yttrium complex supported by a sterically encumbering N-anchored tris-arylphenoxide ligand: Heteroselective ROP of rac-lactide and CO2/epoxide coupling

A C-3-symmetrical yttrium complex [LY(THF)(2)] supported by a sterically encumbering N-anchored tris-arylphenoxide ligand was prepared by the reaction of H3L {L = tris(4,6-di-tert-butyl-2-hydroxybenzyl)amine} and Y[N(TMS)(2)](3) in THF. The experimental results showed that this complex is a good catalyst for the heteroselective ring-opening polymerization (ROP) of rac-lactide, yielding polymers with Pr up to 0.73 under melt conditions at 130 degrees C. In addition, this complex [LY(THF)(2)] can effectively catalyze the coupling reaction of carbon dioxide with cyclohexene oxide using n-Bu4NCl/n-Bu4NBr/n-Bu4NI as a co-catalyst. (C) 2015 Elsevier B.V. All rights reserved.