Preparation of (η5-C5Me5)2Th(bipy) and Its Reactivity toward Small Molecules

Reduction of (η5-C5Me5)2ThCl2 (1) with potassium graphite (KC8) in the presence of 2,2′-bipyridine forms the thorium bipy metallocene (η5-C5Me5)2Th(bipy) (2) in good yield. Complex 2 was fully characterized and reacts with various small molecules. For example, 2 serves as a source for the (η5-C5Me5)2Th(II) fragment when exposed to conjugated alkynes, elemental sulfur and their organic derivatives, diazabutadiene, carbodiimide, CS2, isothiocyanate, and organic azides. Furthermore, treatment of 2 with ketone Ph2CO, thio-ketone Ph2CS, imine PhCH═NPh, and nitrile PhCN results in C–C bond coupling products (η5-C5Me5)2Th[(bipy)(Ph2CO)] (10), (η5-C5Me5)2Th[(bipy)(Ph2CS)] (11), (η5-C5Me5)2Th[(bipy)(PhCHNPh)] (12), and (η5-C5Me5)2Th[(bipy)(PhCN)] (13), respectively, in quantitative conversion.