Triorganoindium reagents

Owing to their pronounced reactivity, alkynylindium reagents typically require short reaction times. The possibility of a stoichiometry-controUed sequential one-pot cross-coupling to 3,4-dichloromaleimides under Pd catalysis has been demonstrated [362]. A distinct chemoselectivity of triorganoindium reagents has been observed favoring replacement of bromo over chloro functionahties in 2,5-dihalopyrimidines [360]. 

Scheme 52 Selective and sequential cross-coupling with triorganoindium reagents [339]...

The 1,4-conjugate addition of triorganoindium to enones is promoted by a catalytic amount of Ni(COD)2 (Scheme 8.71) [100], Allylindium reagents can be used in Pd-catalyzed cross-coupling reaction with aryl halides (Scheme 8.72). The Pd-catalyzed allylic substitution of allyl carbonate produces 1,5-dienes (Scheme 8.73) [101]. The indium-mediated palladium-catalyzed Ullmann-type reductive coupling of aryl halides proceeds in aqueous media under air (Scheme 8.74) [102]. 

TrIORGANOINDIUM COMPOUNDS AS EFFICIENT REAGENTS FOR PALLADIUM-CATALYSED CROSSCOUPLING REACTIONS WITH ARYL AND VINYL ELECTROPHILES... 

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