Calix[4]arenes with a lid in their upper rims: 1,3-dipolar cycloaddition reactions of benzonitrile oxides with 5-allyl-, 5,11-dially- and 5,17-diallylcalix[4]arenes

Abstract

The upper rim substituted mono- and diisoxazolinomethylcalix[4]arenes 9-23 are synthesized in good yields from 1,3-dipolar cycloaddition reactions of para-substituted phenyl nitrileoxides with 5-allyl-, 5,11-diallyl- and 5,17-diallycalix[4]arenes 5-7; the structures of 9-23 are consistent with a 'cone' conformation and the 'vase-with-a-lid' structure of 11 was confirmed by a single-crystal x-ray analysis. Preliminary results show that the monoisoxazolinomethylcalix[4]arene can form an inclusion complex with ammonium cation.