Enantioselective synthesis of a highly potent selective serotonin reuptake inhibitor. An application of imidazolidinone catalysis to the alkylation of indoles with an α,β-disubstituted α,β-unsaturated aldehyde

[GRAPHICS] The synthesis of the highly potent and selective serotonin reuptake inhibitor 1 (BMS-594726) is described. In the key construction step, an enantioselective alkylation of the indole nucleus with an a-branched alpha,beta-unsaturated aldehyde 7 was accomplished utilizing MacMillan's imidazolidinone catalyst 3b. A rationale is presented for the unexpected stereochemical result, as well as the novel reactivity of the alpha-branched substrate.