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Synlett 2005(16): 2492-2494
DOI: 10.1055/s-2005-872694
DOI: 10.1055/s-2005-872694
LETTER
© Georg Thieme Verlag Stuttgart · New York
Hafnium Trifluoromethanesulfonate [Hf(OTf)4]-Catalyzed Conjugate Addition of Indoles to α,β-Enones
Further Information
Received
4 July 2005
Publication Date:
21 September 2005 (online)
Publication History
Publication Date:
21 September 2005 (online)
Abstract
Hafnium trifluoromethanesulfonate [Hf(OTf)4]- and scandium trifluoromethanesulfonate [Sc(OTf)3]-catalyzed conjugated addition of 3-position of indoles to several enones proceeded in acetonitrile as solvent. Especially, Hf(OTf)4 exhibited high catalytic activity and gave the conjugate addition product in good yield.
Key words
hafnium trifluoromethanesulfonate - conjugate additions - Lewis acids - indoles - enones - catalysis
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