Formation of a novel µ3-borate-capped triniobium cluster via hydrolysis of a hydridotris(pyrazol-1-yl)borate ligand
Abstract
The novel µ3-hydroxotrioxoborato-capped cluster [Nb3{µ3-BO3(OH)}(µ-O)3{HB(pz)3}3] 1 has been obtained following evaporation to dryness of aqueous HCl solutions of [Nb3(µ3-Cl)(µ-O)3(OH2)9]4+ and treatment with ethanolic potassium hydridotris(pyrazol-1-yl)borate, K[HB(pz)3]. The capping borate group derives from hydrolysis of a HB(pz)3– ligand in the presence of the aqua precursor. Air oxidation of 1 results in complete fragmentation, loss of the borate cap and reassembly in the form of a rectangular tetranuclear oxo-bridged product.