Synthesis of novel highly functionalized triazole-linked calix[4]resorcinols via click reaction

A single-step acid-catalyzed condensation of resorcinol or 2-methylresorcinol with 4-(prop-2-yn-1-yloxy)benzaldehyde stereoselectively gives exclusively rctt-isomers of new calix[4]- resorcinols in chair conformation bearing four terminal alkyne groups at aromatic substituents. Further alkylation of free hydroxy groups with propargyl bromide affords new calix[4]- resorcinols containing 12 terminal alkyne groups. Subsequent click reaction of these compounds with benzyl azide results in highly functionalized calix[4]resorcinols with 12 triazole- linked branches.