Synthesis of imidazobenzothiazine and primidobenazothiazine derivatives via the classic Ullmann cross-coupling reaction of 1,8-diiodonaphthalene with 1H-benzo[d]imidazole-2-thiols or 2-thiouracils

Abstract

A feasible protocol for the synthesis of imidazobenzothiazine and primidobenazothiazine derivatives via the classic copper(I)-catalyzed Ullmann cross-coupling process has been developed. 1,8-Diiodonaphthalene could couple with 2-mercaptobenzimidazoles or 2-thiouracils to give the corresponding benzo[4,5]imidazo[2,1-b]naphtho[1,8-de][1,3]thiazines and 11H-naphtho[1,8-de]pyrimido[2,1-b][1,3]thiazin-11-ones in moderate yields.

GRAPHICAL ABSTRACT

KEYWORDS:

• Copper-catalyzed
• Ullmann cross-coupling
• imidazobenzothiazines
• primidobenazothiazines

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China (No. 21402079 and 20401094) and the Doctoral Scientific Research Startup Foundation of Liaocheng University (No. 31805403).