Preparation, Characterization, and Reactivity of the Stable Indium Trihydride Complex [InH₃{CN(Mes)C₂H₂N(Mes)}]

Abstract

Reaction of either LiInH 4 or [InH 3 (NMe 3 )] with the Arduengo-type carbene :CN(Mes)-C 2 H 2 N(Mes), Mes ) C 6 H 2 Me 3 -2,4,6, affords the indium trihydride complex [InH 3 {CN(Mes)-C 2 H 2 N(Mes)}]. This compound displays a remarkable thermal stability (dec 115 °C). In solution the products of decomposition depend on the solvent used. In toluene decomposition results in liberation of the free carbene and deposition of indium metal, and in tetrahydrofuran in the presence of indium metal hydrogen transfer occurs to give H 2 CN(Mes)C 2 H 2 N-(Mes) and indium metal, while in dichloromethane, chloride abstraction occurs from the solvent to yield [InCl 3 {CN(Mes)C 2 H 2 N(Mes)}]. A number of related compounds have also been prepared and their structures and properties investigated. These include [GaH 3 {CN-(Mes)C 2 H 2 N(Mes)}], which is the most stable gallium trihydride yet reported, and the indium hydride halide complex [InH 2 Cl{CN(Mes)C 2 H 2 N(Mes)}].

Insertion of Group 12–16 Hydrides into NHCs: A Theoretical Investigation

“…There remains significant debate around the stability of In and Tl trihydrides, which have recently been synthesized in the gas phase but despite early claims by Wiberg of their isolation (that could not be reproduced), it would appear that solid phase isolation of InH 3 and TlH 3 is unlikely. Nevertheless, the heavier trihydrides are included for comparison in the present study, and may potentially be isolatable as adducts with NHCs with the reaction of lithium complexes such as LiInH 4 , which Jones and co‐workers employed in the isolation of an NHC–InH 3 adduct …”

“…Numerous studies have also demonstrated that group 13 hydrides can be stabilized by NHCs, including the boron mediated reactions reported by Schaefer, Schleyer and Robinson to stabilize both a B=B double bond and a bridged BH 2 complex . Extensive work has been carried out by Jones and co‐workers in the stabilization of the majority of the group 13 hydrides including Al, Ga, In and Tl . Other notable outcomes include the AlH 3 adduct of NHC Mes reported by Cole and co‐workers, the AlMe 3 adduct of NHC t Bu by Dagorne, and the gallium‐chloride species isolated by Nolan …”

The Reactivity of Primary and Secondary Amines, Secondary Phosphanes and N‐Heterocyclic Carbenes towards Group‐13 Metal(I) Halides

“…[15] The crystal structure of the cationic component of 8 is shown in Figure 7 . [16] Interestingly, both the terminal and bridging InϪCl bonds (2.567 Å av. and 2.872 Å av., respectively) are considerably longer than the norms for such bonds (2.45 and 2.59 Å ) [17] and indeed, the bridging Cl Ϫ ligand can be thought of as only having an interaction (2) 2.592(2), In(1)ϪO(1) 2.174 (7), In(1)ϪC(1) 2.233 (7), In(1)ϪC (8) 2.235 (7), In(2)ϪCl(1) 2.921(2), In(2)ϪCl(3) 2.542(2), In (2)ϪO (1) 2.172 (7), In(2)ϪC (15) 2.221 (7), In(2)ϪC (22) 2.218(8); In(1)ϪO(1)ϪIn (2) 113.6(3), In(1)ϪCl(1)ϪIn (2) 78.54(5), Cl (2)ϪIn (1)ϪC(1) 94.64(18), Cl(2)ϪIn(1)ϪC (8) 91.51(19), C(1)ϪIn(1)ϪC (8) 109.2(3), Cl(1)ϪIn(1)ϪCl (2) 172.16 (6) (2)ϪCl(1) 81.1(2), Cl(1)ϪIn (2)ϪCl (3) 173.72 (7), N(1)ϪC(1)ϪN (2) 105.5 (6), N(3)ϪC (8)ϪN (4) 105.6(6), N(5)ϪC (15)ϪN (6) 103.9 (6), N(7)ϪC(22)ϪN (8) 104.9(6) with the indium centres.…”

Kinetic Control over the Thermal Stability of the InH Bond: Synthesis and Characterization of Amido Indium Hydride Complexes

“…[4] Most success has been had with highly nucleophilic N-heterocyclic carbenes (NHCs), which form strong C À In dative bonds and discourage the formation of intermolecular In-H-In bridges by providing a degree of steric shielding to the InH 3 fragment. [5] A number of alkyl, halogen, phosphido and gallyl indium hydride complexes [4,6] have also been prepared and are finding applications in inorganic [4] and organic synthesis. [7] For these applications to expand, greater control over the thermal stability of indium hydride complexes is required.…”