A theoretical study on synthesis mechanisms of alpha,beta-unsaturated carbon gamma-amino ester catalyzed by PPh3

作者：Xu, Hao; Li, Yue; Zhu, Yanyan^*; Shang, Xuchen; Zhu, Zhenhua; Tang, Mingsheng

来源：Structural Chemistry, 2017, 28(6): 1959-1968.

DOI：10.1007/s11224-017-0990-3

• Reaction mechanism
• Triphenylphosphine
• Amino ester
• DFT

In this paper, generation mechanism of alpha,beta-unsaturated carbon gamma-amino esters catalyzed by triphenylphosphine (PPh3) have been investigated using density functional theory (DFT). Two possible mechanisms (Mechanism A and Mechanism B) are proposed, in which there are three possible reaction pathways (Path A1/A2/A3 in Mechanism A and Path B1/B2/B3 in Mechanism B) except for the generation of the intermediate M1. The calculated results demonstrate that the energy favorable pathways (Path A2 and Path B2) include three process: the first step is an intermolecular proton transfer accompanied by a nucleophilic attack, the second step is an intramolecular proton transfer process, and the last step is the dissociation of PPh3 and the product generation. Furthermore, the reaction pathway associated with the E-isomer is the most favorable pathway and leads to the main product (E-P), which is in good agreement with the experimental results. This work might be helpful for understanding the significant roles of catalyst PPh3 and thus provide valuable insights on the rational design of potential catalysts for this kind of reactions.

• 出版日期2017-12
• 单位郑州大学