Mechanistic investigation of zwitterionic MOF-catalyzed enyne annulation using UNLPF-14-MnⅢ as catalyst

作者：Taotao Liu; Ruihong Duan; Yanyan Wang; Shijun Li; Lingbo Qu; Jinshuai Song^*; Qiang Liu^*; Yu Lan^*

来源：Chinese Chemical Letters, 2022, 33(09): 4281-4286.

Hybrid quantum mechanics/molecular mechanics calculations were performed to elucidate how[MnⅢ porphyrin]+X--based metal-organic frameworks(MOFs) catalyze the [2 + 1] cycloisomerization of enynes and why zwitterionic MOFs exhibit strong activity in Lewis acid catalysis. The calculations showed that zwitterionic MOFs have a “pure cationic active center” leading to a concerted nucleophilic attack pathway with lower barriers. In contrast, metals with coordinating anions have reduced electrophilicity,resulting in a stepwise radical-type pathway with much higher barriers. Further calculations showed the nature of catalysis was strongly depended on the charge on the anion ligand. A good linear relationship between the NPA charge and barrier was found, and verified by 73 anions with small derivations, which presents a universal adaptive character for various coordinated anions.

• 单位
  郑州大学; 清华大学