Role of polar solvents for the synthesis of pillar[6]arenes†
Abstract
An efficient procedure for the synthesis of pillar[6]arenes has been developed. The procedure involves the condensation of 1,4-dialkoxybenzenes and paraformaldehyde in the presence of a catalytic amount of H2SO4 or BF3·OEt2 in polar solvent media (acetonitrile, ethyl alcohol, acetone etc.). In all cases the interaction afforded pillar[6]arenes in high yields.