Al-MCM-41 as a mild and ecofriendly catalyst for Michael addition of indole to α,β-unsaturated ketones
摘要:
Mesoporous Al-MCM-41 catalyzes the chemoselective Michael addition reaction between indoles and alpha,beta-unsaturated ketones to afford beta-indolylketones at room temperature with excellent yields. The higher catalytic activity is attributed to Lewis acidic Al and the large surface area. The catalyst is readily recovered and reused more than six times without loss in its catalytic activity. The substitution at the indole nucleus occurs exclusively at the 3-position and N-alkylation products are not observed. (C) 2012 Elsevier B.V. All rights reserved.