Reductive and oxidative reactions of calix[4]arene derivatives

Reductive cleavage of 25,26,27,28-tetramethoxy-p-tert-butylcalix[4]arene with K results in the formation of 26,28-dimethoxy-p-t-butylcalix[4]arene. The reaction of 25,27-dihydroxycalix[4]arene with NO₂BF₄ in acetonitrile results in its oxidation to calixdiquinone 6.