文摘
We have developed a novel synthetic method that enables the preparation of functional derivatives of heptiptycene, i.e., cavitands with two juxtaposed cavities. The homocoupling of bicyclic dibromoalkenes is promoted by Pd(OAc)2 (10%) in dioxane (100 掳C) to give cyclotrimers in 27鈥?7% yield under optimized reaction conditions (Ph3P, K2CO3, n-Bu4NBr, N2, 4 脜 MS). These dual-cavity baskets show a strong 蟺 鈫?蟺* absorption at 241 nm (蔚 = 939 000 M鈥? cm鈥?), along with a subsequent fluorescence emission at 305 nm.