A series of basket-shaped hosts with ester-crown handles have been synthesized by treating oligoethylene glycol bischloroacetates [ClCH2CO(OCH2CH2)nOCOCH2 Cl, n = 1, 2, 3, 4] and 1,2-bis(hydroxyethoxy)benzene bischloroacetates with a diphenylglycoluril-based molecular clip, 1,3:4,6-bis(3,6-dihydroxy-1,2-xylylene)tetrahydro-3a, 6a-diphenylimidazo[5,5]imidazole-2,5(1H, 3H)-dione (1), in dimethyl sulfoxide using K2CO3 as a base in yields of 15, 35, 40, 38, and 20%. Their structures were identified by nuclear magnetic resonance and mass spectrum. The reaction conditions were also studied and optimized. |