Synthesis of 1,3- and 1,4-Diacetylamido-Bridged p-tert-Butylcalix[7]arenes

Abstract 1,3-Oxy-(2′,7′-dioxo-3′,6′-diazaoctamethylene)oxy-bridged P-TERT-butylcalix[7]arenes and 1,4-oxy-(2′,8′-dioxo-3′,7′-diazanonamethylene)oxy-bridged P-TERT-butylcalix[7]arenes were synthesized regioselectively by a base-promoted alkylation of P-TERT-butylcalix[7]arene with dichloro bridging agents [ClCH 2 CONH(CH 2 ) n NHCOCH 2 Cl, n = 2, 3], respectively. How­ever, using ClCH 2 CONH(CH 2 ) 6 NHCOCH 2 Cl as a bridging ­reagent, a mixture of 1,3- and 1,4-bridged P-TERT-butylcalix[7]arene derivatives were obtained. The bridging pattern and the yields of the products were highly sensitive to the length of bridging reagent and the base employed.