Novel cerium(IV)-diolate complex with a 13-nuclear cerium(IV)-oxo core: Synthesis, molecular structure and catalytic property for ε-caprolactone-polymerization

The reaction of Ce(O t Bu) 2 (NO 3 ) 2 , prepared in situ from (NH 4 ) 2 Ce(NO 3 ) 6 and t BuONa in a 1:4   M ratio in THF, and N -phenyldiethanolamine (C 6 H 5 )N(CH 2 CH 2 OH) 2 in a 1:1   M ratio led to a brown solution, to which 1,10-phenanthroline (phen) was added. Yellow crystals of Ce(NO 3 ) 3 (phen) 2 and red crystals of Ce 13 O 8 [(OCH 2 CH 2 ) 2 N(C 6 H 5 )] 18 ( 1 ) were produced respectively at 40   °C. Complex 1 is a novel polynuclear cerium(IV)-diolate compound with an 18 N-phenylaminediethanolate shell and a 13-nuclear cerium(IV)-oxo core. It catalyzed the polymerization of ε -caprolactone (CL) to produce PCL in very narrow molecular weight distribution.