Molecular receptors with the calix[4]arene substructure. Synthesis of derivatives with mixed ligating functional groups

Abstract
p-t-Butylcalix[4]arene has been derivatised regioselectively at positions 1 and 3 of the four equivalent phenolic groups using electrophiles such as ethyl bromoacetate, chloroacetone, bromopinacolone, and chloroacetonitrile; the products are useful precursors for the synthesis of tetrasubstituted calixarenes with mixed ligating functional groups.