Preparation of methylene-substituted calixarenes

Abstract

The different synthetic approaches for the preparation of “classical” calixarenes with one, part, or all bridges chemically modified are reviewed. The methods include the cyclization of fragments, the homologous anionic ortho Fries rearrangement, the spirodienone method, the lithiation/alkylation approach, the oxidation of the bridges followed by reaction of the carbonyl units with organolithium reagents, and the bromination of the bridges followed by reaction with nucleophiles.