Asymmetric Friedel-Crafts alkylation of indole with chalcones catalyzed by chiral phosphoric acids.
The reaction of indole with chalcones, to give Michael-type adducts, was found to occur with good efficiency (up to 98% yield) and moderate enantioselectivity (up to 52% e.e.) in the presence of a chiral BINOL-based phosphoric acid. Furthermore, the alkylation products can be obtained in much higher e.e.s after one only crystallization.
Scettri
Arrigo
A
Dipartimento di Chimica, Università di Salerno, Via Ponte Don Melillo 84084, Fisciano,Salerno, Italy. scettri@unisa.it
Villano
Rosaria
R
Acocella
Maria Rosaria
MR
D000478:Alkylation; D002384:Catalysis; D047188:Chalcones / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D015394:Molecular Structure; D010756:Phosphoric Acids / Q000737:chemistry*; D013237:Stereoisomerism
D047188:Chalcones; D007211:Indoles; D010756:Phosphoric Acids; C030374:indole
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