The crystallization of K [ I ~I H ( C H ~C M ~~) ~]from heptane in the presence of silicone grease led to the formation of the title compound, in which one potassium cation is surrounded by a planar ~yclo-(Me~SiO)~ ligand; K+...O distances range from 2.86(3) to 2.99(4) A.We have previously reported the preparation of K+ [InH( CH2CMe3)3-] along with a crystallographic study of the related dinuclear species K+[H{ In(CH2CMe3)3}2-]. * Attempts to crystallize K+[InH(CH2CMe3)3-] from pentane at low temperature produced large, colourless, transparent, rectangular crystals in the mother liquor. When the pentane was removed. the crystals became opaque and shattered. In an attempt to protect the material from solvent loss, the following crystallization procedure was used. A sample of K + [ I I I H ( C H ~C M ~~) ~-] and a small amount of Dow Corning high-vacuum silicone grease (intended to protect any crystals thus grown) were placed in a tube equipped with a Solv-Seal joint. Heptane was added by vacuum distillation. The solid dissolved as the mixture was warmed from -196 "C to room temp. over 2 h. Needle shaped single crystals formed overnight. The crystal used for the X-ray crystallographic study was cut from a larger crystal and mounted in a thin-walled capillary tube. [ N . B. All materials were handled under purified argon or in vacuo. Organoindium hydrides are

An organoindium phosphide which incorporates two phosphido moieties in the same molecule, (Me3CCH2)2InP(t-Bu)2In(CH2CMe3)2PPh2 (1), has been synthesized in good yield from [(Me3CCH2)2InP(t-Bu)2]2 and (Me3CCH2)2InPPh2 in pentane solution and fully characterized. The compound exists as a single compound in the solid state according to an X-ray structural study but is in equilibrium with the starting compounds in benzene solution according to 1H and 31P NMR spectral data.

A 1:1 mixture of In(CH2CMe3)3 and HP(i-Pr)2 at room temperature undergoes a very slow hydrocarbon elimination reaction to form [(Me3CCH2)2InP(i-Pr)2]2 and neopentane. The indium phosphide [(Me3CCH2)2InP(i-Pr)2]2 has also been prepared by reacting KIn(CH2CMe3)3H with ClP(i-Pr)2 in pentane. When pentane solutions of these reagents were combined at −78 °C and then maintained at ∼20 °C for 2 days, [(Me3CCH2)2InP(i-Pr)2]2, (Me3CCH2)3In·P(H)(i-Pr)2, (Me3CCH2)3In·P2(i-Pr)4, (Me3CCH2)3In·P(CH2CMe3)(i-Pr)2, H2, indium metal, and KCl were observed. The formation of all products is explained by a set of experimentally verified reactions. An X-ray structural study of [(Me3CCH2)2InP(i-Pr)2]2 shows each molecule to have an unusual puckered four-membered In2P2 core.

The reaction between KIn(CH 2 CMe 3 ) 3 H and ClPPh 2 in pentane or benzene produces significant yields of two indium-phosphorus compounds, (Me 3 CCH 2 ) 2 -InPPh 2 and (Me 3 CCH 2 ) 3 In‚P(CH 2 CMe 3 )Ph 2 . This unexpected adduct incorporates a neopentyl group that was originally a substituent on the indium reagent. The other products of the reaction are CMe 4 , H 2 , and KCl. The formation of all products is explained by a set of experimentally verified reactions.