Synthesis 2022; 54(24): 5434-5444
DOI: 10.1055/a-1938-2521
feature

Unexpected Pyridinyl Group Mediated Metal-Free Wacker-Type Oxidation en Route to Pyrido[2,1-a]isoindol-5-ium Salts

Dong Shi
,
Tao Zeng
,
Xin Lei
,
Xiaotong Wu
,
Mansirun Li
,
Yandong Zhang
Financial support from the National Natural Science Foundation of China (Nos. 22071205, 21772164, and 21572187), the National Fund for Fostering Talents of Basic Science (NFFTBS, J1310024), and the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT) is acknowledged.


Abstract

A two-step approach to rapidly access a diverse array of pyrido[2,1-a]isoindol-5-ium salts from 2-pyridinylstyrenes through an unprecedented pyridinyl group mediated metal-free Wacker-type oxidation and an acid-mediated cyclization has been developed. As a part of the mechanistic investigation of this novel Wacker-type oxidation, the abnormal instability and reactivity of the pyrido[2,1-a]isoindole intermediates were studied through DFT calculations.

Supporting Information



Publication History

Received: 11 August 2022

Accepted after revision: 07 September 2022

Accepted Manuscript online:
07 September 2022

Article published online:
10 October 2022

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