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Electric field-catalyzed single-molecule Diels-Alder reaction dynamics.

ABSTRACT: Precise time trajectories and detailed reaction pathways of the Diels-Alder reaction were directly observed using accurate single-molecule detection on an in situ label-free single-molecule electrical detection platform. This study demonstrates the well-accepted concerted mechanism and clarifies the role of charge transfer complexes with endo or exo configurations on the reaction path. An unprecedented stepwise pathway was verified at high temperatures in a high-voltage electric field. Experiments and theoretical results revealed an electric field-catalyzed mechanism that shows the presence of a zwitterionic intermediate with one bond formation and variation of concerted and stepwise reactions by the strength of the electric field, thus establishing a previously unidentified approach for mechanistic control by electric field catalysis.

SUBMITTER: Yang C

PROVIDER: S-EPMC7817103 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Electric field-catalyzed single-molecule Diels-Alder reaction dynamics.

Yang Chen C Liu Zitong Z Li Yanwei Y Zhou Shuyao S Lu Chenxi C Guo Yilin Y Ramirez Melissa M Zhang Qingzhu Q Li Yu Y Liu Zhirong Z Houk K N KN Zhang Deqing D Guo Xuefeng X

Science advances 20210120 4

Precise time trajectories and detailed reaction pathways of the Diels-Alder reaction were directly observed using accurate single-molecule detection on an in situ label-free single-molecule electrical detection platform. This study demonstrates the well-accepted concerted mechanism and clarifies the role of charge transfer complexes with <i>endo</i> or <i>exo</i> configurations on the reaction path. An unprecedented stepwise pathway was verified at high temperatures in a high-voltage electric fi ...[more]

PMID: 33523936

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