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Gallium hydride and monovalent indium compounds that feature tris(pyrazolyl)hydroborate ligands
Kevin Yurkerwich1, Yi Rong, Gerard Parkin
1Department of Chemistry, Columbia University, NY 10027, USA.
Abstract:
The tris(pyrazolyl)hydroborate compounds [tris(3,5-dimethyl-1H-pyrazol-1-yl-κN(2))hydroborato]indium(I), [In(C15H22BN6)], abbreviated as [Tp(Me2)]In, and [tris(3-tert-butyl-5-methyl-1H-pyrazol-1-yl-κN(2))hydroborato]indium(I), [In(C24H40BN6)], abbreviated as [Tp(Bu(t),Me)]In, represent well defined examples of three-coordinate monovalent indium. In both compounds, the geometry at indium is pyramidal and natural bond orbital (NBO) calculations indicate that the indium lone pair occupies an orbital that is primarily 5s in character. The trivalent gallium hydride compound hydrido[tris(3-tert-butyl-5-methyl-1H-pyrazol-1-yl-κN(2))hydroborato]gallium(III) tetrachloridogallium(III), [Ga(C24H40BN6)H][GaCl4], abbreviated as {[Tp(Bu(t),Me)]GaH}[GaCl4], is obtained via reaction of [Tp(Bu(t),Me)]Tl with [HGaCl2]2, and the Ga-H bond length of 1.49 (6) Å compares favorably with the mean value of 1.50 Å for structurally characterized gallium hydride compounds that are listed in the Cambridge Structural Database.
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