Two tetranuclear Tb(III)-based clusters: Crystal structures and effectively catalyze the cycloaddition of CO2 with epoxides

Two new and interesting tetranuclear Tb(III)-based clusters [Tb 4 (NO 3 ) 2 (acac) 4 (HL) 2 (CH 3 OH) 2 ]·2(CH 3 CN)] ( 1 ) and [Tb 4 (NO 3 ) 2 (acac) 4 (L) 2 (CH 3 CH 2 OH) 2 ] ( 2 ) (H 4 L1 = 2-(hydroxymethyl)-2-(((2-hydroxynaphthalen-1-yl)methylene)amino)propane-1,3-diol); H 3 L2 = 2-(((2-hydroxynaphthalen-1-yl)methylene)amino)-2-methylpropane-1,3-diol; and Hacac = acetylacetone) have been successfully synthesized by using two polydentate Schiff base ligands (H 3 L2 and H 4 L1). The crystal structures, fluorescent properties, magnetic properties and catalytic properties of the two clusters 1 and 2 have been systematically studied. Interestingly, both clusters 1 and 2 can catalyze the cycloaddition of CO 2 with epoxides with high efficiency under mild conditions; and cluster 1 as a catalyst could be reused at least three times without obvious loss of catalytic performance.