New hexazirconium clusters containing hydrogen atoms

Reduction of ZrBr4 with HSnBu3 yielded a blue solid. When this blue solid w as treated with PMe3, a hexanuclear cluster [Zr6Br14H4(PMe3)(4)] (2) was is olated. Reaction of the blue solid with [PPh4]Br in CH2Cl2 resulted in the formation of a paramagnetic and unstable cluster anion, [Zr6Br18H5](2-) (3' ), which disproportionated to form a new cluster anion, [Zr6Br18H5](3-) (4' ) and some Zr(IV) species. Compounds containing 4' can also be obtained fro m reaction of the blue solid with Br- in MeCN. Reduction of ZrCl4 with HSnB u3 gave a red-brown solid, and [Zr6Cl14H4(AsMe3)(4)] (9) and [Zr5Cl12H4(AsM e3)(5)] (8) were obtained by reaction of the red-brown solid with AsMe3. No cluster compounds containing amine ligands were obtained in the reaction o f the red-brown solid with amines; only compounds containing the [Zr6Cl18H5 ](3-) anion and ammonium cations were isolated. Altogether ten products wer e characterized by single crystal X-ray diffraction and where possible, by H-1 NMR studies.