Organoindium halides

Supramolecular self-organization, with different amounts of complexity based upon dative bonds (see Section 3.2.3.1) and secondary bonds, is observed for organoindium halides. Long indium-halogen interatomic distances (although shorter than the expected van der Waals distance (ca. 3.8 A for In- -Cl)) are observed for most structurally characterized organoindium halides. 

Dimethylindium chloride, Me2lnCl, forms double-chain ribbons which interact via additional secondary bonds, resulting in a supramolecular two-dimensional array, 31 [138]. The In-Cl bonds within the ribbon are somewhat elongated (primary In-Cl 2.673 A secondary In- -Cl 2.945 and 2.954 A) and the interatomic distances between ribbons are rather long (3.450 A), indicating secondary bonding character. 

In the neopentyl-trimethylsilylmethyl derivative [(Bu CH2)(Me3SiCH2)InCl] dimeric tectons formed by dative bonding (In-Cl 2.572 and 2.659 A) are self-organized in ladder supramolecular arrays, 32, via secondary bonding (In --Cl 3.528 A) [139]. The indium atom is five-coordinate (distorted trigonal bipyramidal). 

A slightly different structural motif is observed in the solid state structure of [MeInCl2]x. In this compound the supramolecular self-assembly is maintained only by secondary In Cl bonds which connect the tectons in a ladder-type ribbon, 33 [140]. 

In mesitylindium diiodide, [Meslnl2]2, both halogens are involved in the inter-molecular association this results in a new supramolecular motif, 34 [141]. 

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As synthetic reagents, stericaUy encumbered organoindium halides have been nsed in transmetalation reactions to prepare the first example of a monomeric base-free group 13 hydride complex (Scheme 2). ... 

The preparation of inert organoindium halides with sterically demanding ligands such as Mes (2,4,6-Me3C6H2), Trip (2,4,6-iPr3C6H2), or Mes (2,4,6-tBuC6H2), and so on has become a recent trend. Most of these derivatives are prepared via the normal synthetic routes outlined earlier. A... 

Organoindium halides are formed nearly quantitatively by redistribution between In(III) halides and Rsin. Both mono- and dihalides are produced, depending on the stoichiometry ... 

Redistribution also takes place between In(III) halides and organoindium halides or between different organoindium halides. Methylindium iodides are produced in this manner ... 

Organoindium halides can readily be prepared by many of the synthetic methods outlined for the preparation of organoindium derivatives, but with stoichiometric control to afford the organoindium halide derivative. For example, (a) reaction of InXa with less than three equivalents of a lithium or Grignard reagent (equations 12-13), (b) reaction of Rsin with HX, which proceeds by elimination of a simple organic moiety (equation 14), (c) a redistribution reaction between InXa and Rain (equations 15-16). 

Habeeb, J.J., Said, F.F. and Tuck, D.G. (1980) Coordination compounds of indium. Part 36. The direct electrochemical synthesis of neutral and anionic organoindium halides , 7. OrganometaL Chem., 190, 325-335. 

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