Regioselective synthesis of indazolo[2,3- a]quinazolines enabled by I2/S-facilitated annulation relay dehydrogenative aromatization of cyclohexanones

Qinghe Gao; Yimei Guo; Penghui Cao; Guangping Fan; Yongtao Xu

doi:10.1039/d3cc04698b

Regioselective synthesis of indazolo[2,3- a]quinazolines enabled by I₂/S-facilitated annulation relay dehydrogenative aromatization of cyclohexanones

Chem Commun (Camb). 2023 Nov 21;59(93):13835-13838. doi: 10.1039/d3cc04698b.

Authors

Qinghe Gao¹, Yimei Guo¹, Penghui Cao¹, Guangping Fan¹, Yongtao Xu²

Affiliations

¹ School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P. R. China. gao_qinghe@xxmu.edu.cn.
² School of Medical Engineering, Xinxiang Key Laboratory of Biomedical Information Research, Henan International Joint Laboratory of Neural Information analysis and Drug Intelligent Design, Xinxiang Medical University, Xinxiang, Henan 453003, P. R. China. yxu@xxmu.edu.cn.

PMID: 37921123
DOI: 10.1039/d3cc04698b

Abstract

A method for concise and efficient synthesis of indazolo[2,3-a]quinazolines has been developed via a sequential annulation of 3-aminoindazoles and dehydrogenative aromatization of cyclohexanones. This high regioselectivity is attributed to the fact that the Mannich reaction is superior to the aldol reaction in this system. It is worth mentioning that this convenient process is successfully extended to 3-aminopyrazoles for assembling another class of medicinally prevalent pyrazolo[1,5-a]quinazolines.