Synthesis 2023; 55(16): 2570-2580
DOI: 10.1055/a-2058-0119
paper

I2/DTBP Promoted Synthesis of C3-Carbonylated Imidazopyridines from Chromones and 2-Aminopyridines via (3+2) Cycloaddition

Qiang Huang
a   School of Pharmacy, Zunyi Medical University, Zunyi, Guizhou 563000, P. R. of China
b   The Key Laboratory of Clinical Pharmacy of Zunyi City, Zunyi Medical University, Zunyi, Guizhou 563006, P. R. of China
,
Lvjia Wu
a   School of Pharmacy, Zunyi Medical University, Zunyi, Guizhou 563000, P. R. of China
,
Jihai Shi
a   School of Pharmacy, Zunyi Medical University, Zunyi, Guizhou 563000, P. R. of China
,
Jiangdong Li
c   School of Public Health, Zunyi Medical University, Zunyi, Guizhou 563000, P. R. of China
,
Wei Lu
a   School of Pharmacy, Zunyi Medical University, Zunyi, Guizhou 563000, P. R. of China
,
Fushan Tang
a   School of Pharmacy, Zunyi Medical University, Zunyi, Guizhou 563000, P. R. of China
b   The Key Laboratory of Clinical Pharmacy of Zunyi City, Zunyi Medical University, Zunyi, Guizhou 563006, P. R. of China
,
Lei Zhu
a   School of Pharmacy, Zunyi Medical University, Zunyi, Guizhou 563000, P. R. of China
b   The Key Laboratory of Clinical Pharmacy of Zunyi City, Zunyi Medical University, Zunyi, Guizhou 563006, P. R. of China
,
Wenwu Zhong
d   Chongqing Medical and Pharmaceutical College, Chongqing 401331, P. R. of China
,
Changkuo Zhao
a   School of Pharmacy, Zunyi Medical University, Zunyi, Guizhou 563000, P. R. of China
› Author Affiliations
Financial support from the Academic Cultivation and Innovation Exploration Special Project of Zunyi Medical University in 2018 (No. [2018]5772-013, CK-1149-011), the Young Talents Growth Project of the Higher Education Institutions of Guizhou Province (No. KY[2021]221) and the Natural Science Foundation of Guizhou Province (No. ZK[2022]592) is gratefully acknowledged.


Abstract

An I2/DTBP-promoted (3+2) cycloaddition reaction of 2-aminopyridines and chromones is reported. The work provides a simple and efficient approach to access imidazopyridines scaffold in moderate to good yields. I2/DTBP as an initiator and oxidant was used to realize the tandem (3+2) cycloaddition/oxidative aromatization. Available starting materials, excellent functional-group tolerance, potential drug activity of the products, and application in production on a gram scale are advantageous features of this strategy. Moreover, the obtained products provide a key active fragment for the synthesis of cabozantinib analogues, which has the potential to be developed as an anticancer agent.

Supporting Information



Publication History

Received: 21 December 2022

Accepted after revision: 20 March 2023

Accepted Manuscript online:
20 March 2023

Article published online:
19 April 2023

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