Organoindium formation

The nucleophilic reaction of Grignard reagents with azetidin-2,3-dione 270 yielded mainly fA-3-hydroxyazetidin-2-ones 271 (Equation 76) <2006S115>. A regio- and stereoselective reaction of azetidine-2,3-dione 272 with an organoindium compound led to the formation of azetidin-2-one-tethered homoallylic alcohol 273 (Equation 77), which has been used as precursor of spirocyclic azetidin-2-ones <2004TL6429>. 

Organoindium substances are important, especially for the production of materials by metal-organic chemical vapor-phase deposition (MOCVD). This technique involves the thermal decomposition of mixtures of an organoindium compound and a compound such as phosphine (PH3), leading to the deposition of ordered layers of InP. The resulting compound can be used in the formation of semiconductors and solid-state optical devices (similar to silicon), see also Inorganic Chemistry. 

The zinc-mediated Reformatsky reaction is one of the classical methods for carbon-carbon bond formation. To date, various main group metals and transition metals have been used for this reaction. Rieke s activated indium powder mediates readily the coupling of ethyl a-bromoacetate and a variety of carbonyl compounds yielding /3-hydroxy esters in good yields (Scheme 87).3 Later, commercially available indium powder has been found to be equally effective for the indium-based Reformatsky reaction in THF.28 This indium Reformatsky reaction is accelerated by ultrasound irradiation (Scheme 88).322,323 Indium(i) iodide also mediates the Reformatsky reaction of aldehydes and ketones to give /3-hydroxy esters, presumably via organoindium(m) diiodide (Scheme 89).27... 

Scheme 3 Formation of organoindium carbene halide derivatives...

A method for iV-alkylation of a-amino esters by RCHO and R l employing In/Ag and InCl3 in aqueous MeOH has been developed. It involves formation of organoindium reagents and imines, and their mutual reaction. 

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