Synthesis of Functionalized Indoles with a Trifluoromethy-Substituted Stereogenic Tertiary Carbon Atom Through an Enantioselective Friedel-Crafts Alkylation with beta-Trifluoromethyl-alpha, beta-enones

[EN] Chiral complexes of BINOL-based ligands with zirconium tert-butoxide catalyze the Friedel-Crafts alkylation reaction of indoles with beta-trifluoromethyl-alpha,beta-unsaturated ketones to give functionalized indoles with an asymmetric tertiary carbon center attached to a trifluoromethyl group. The reaction can be applied to a large number of substituted alpha-trifluoromethyl enones and substituted indoles. The expected products were obtained with good yields and ees of up to 99%.Financial support from the Ministerio de Ciencia e Innovacion and FEDER (grants CTQ2006-14199 and CTQ2009-13083) and from Generalitat Valenciana (ACOMP/2009/338) is acknowledged. CV. thanks the Generalitat Valenciana for a pre-doctoral grant.Blay, G.; Fernández, I.; Muñoz Roca, MDC.; Pedro, JR.; Vila, C. (2010). 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