Trisulfonamide calixarene-catalysed Michael addition to nitroalkenes†
We describe the application of a novel family of trisulfonamide (TSA) calixarenes in general acid catalysis. Hydrogen-bonding interactions between acidic TSA and methanol boosted the reactivity of the Michael addition of indoles to nitroalkene derivatives. The transformation occurs at a low catalyst loading of 5 mol%, allowing for the synthesis of nitroalkanes with good yields and functional group tolerance.
- This article is part of the themed collection: Catalysis & biocatalysis in OBC