Efficient Hydride and Pyrazolyl Redistribution upon Thermolysis of a Calcium Complex Containing Dihydrobis(pyrazolyl)borate Ligands

Thermolysis of CaBp2(THF)2 (THF = tetrahydrofuran) at 190–200 °C and 0.05 Torr leads to a redistribution reaction to afford CaTp2 (90%) and CaTp(BH4) (84%). Treatment of CaTp(BH4) with THF affords CaTp(BH4)(THF)2 and [CaTp(BH4)(THF)]4, both of which were structurally characterized. Methanolysis or ethanolysis/hydrolysis of the BH4–-containing complexes affords [TpCa(HOMe)2(μ4-B(OMe)4)Ca(HOMe)2Tp][B(OMe)4] and [{TpCa}3{μ6-B(OB(OEt)3)3]·EtOH.