INDIUM(III) DIHYDROBIS(PYRAZOLYL)BORATE COMPLEXES - CRYSTAL AND MOLECULAR-STRUCTURES OF ([H2B(PZ)2]IN(CH3)CL)2 AND [H2B(PZ)2]IN(CH3)2

The reaction of InCl3 with 1, 2 and 3 equiv of K[H2B(pz)2] (pz = pyrazolyl ring) yields [H2B(pz)2]InCl2 (1), [H2B(pz)2]2InCl (2), and [H2B(pz)2]3In (3), respectively. The methyl complexes [H2B(pz)2]2InCH3 (4)and [H2B(pz)2]In(CH3)Cl (5) are prepared from the reaction of CH3InCl2 with 2 and 1 equiv of K[H2B(pz)2],respectively. Complex 5 is also formed by an exchange reaction between (CH3)2InCl and 2. The dimethyl complex [H2B(pz)2]In(CH3)2 (6) is prepared by the reaction of (CH3)2InCl and 1 equiv of K[H2B(pz)2]. The reaction of InCl3 with 1 equiv of Na(O2CCH3) and 2 equiv of K[H2B(pz)2] yields [H2B(pz)2]2In(02CCH3) (7). Complex 7 can also be prepared by the reaction of complexes 3 and 4 with CH3C02H and by the reaction of 2 with Na(02CCH3). {[H2B(pz)2]In(CH3)(O2CCH3)}2 (8) is formed by the reaction of K[H2B(pz)2] and Na(O2CCH3) with CH3InCl2. Complex 8 can also be obtained from the reaction of 6 with CH3CO2H. Compounds 2-8 are stable to air for extended periods of time. Molecular weight studies in benzene indicate that complexes 4-6 are monomeric. Molecular weight determinations for 7 in benzene yield a value between a monomer and a dimer. Complex 8 is a dimer in benzene solution. An X-ray crystallographic study shows that 5 is dimeric in the solid state with a highly asymmetric In (µ-01)2 bridging unit and a distortedtrigonal-bipyramidal geometry about the indium: triclinic, P1, a = 7.6001 (14) Å, b = 8.6133 (14) Å, c = 19.960 (4) Å, α = 79.086 (15)°,β = 85.966 (16)°, γ = 67.340 (13)°, V = 1184.0 (3) Å3, Z = 4, R(F)=2.80%. The solid-state structure of 6 is monomeric with a distorted-tetrahedral geometry about indium: orthorhombic, Pn21a, a = 13.482 (6) Å, b = 9.008 (5) Å, c = 9.761 (4) Å, V = 1179.7 (8) Å3, Z = 4, R(F) = 2.45%. © 1990, American Chemical Society. All rights reserved.