Enantioselective Friedel‐Crafts Alkylation of Indoles with
<i>α, β</i>
‐Unsaturated Aldehydes Catalyzed by Recyclable Second‐generation MacMillan Catalysts
作者:Mohd Jubair Aalam、Deepa、Surendra Singh
DOI:10.1002/ejoc.202200978
日期:2022.11.18
An efficient protocol for enantioselective Friedel-Crafts alkylation reaction was develoved using recoverable second-generation MacMillan catalysts in the presence of trifluoroacetic acid as a co-catalyst.
development of an improved organocatalyst, N-isopropylated bipyrrolidine 2a, for the asymmetric Friedel–Craftsalkylation of indoles with α,β-unsaturated aldehydes has been presented. The new organocatalyst readily facilitates the enantioselectivealkylation reaction, providing 3-alkylated indoles in good to high yields (62–89%) with high levels of enantioselectivity (80–93% ee) using only 2 mol% of catalyst