Green Protocol for the Novel Synthesis of Thiochromeno[4,3- b]pyridine and Chromeno[4,3- b]pyridine Derivatives Utilizing a High-Pressure System

Haider Behbehani; Kamal M Dawood; Fatemah A Aryan; Hamada Mohamed Ibrahim

doi:10.1021/acsomega.1c05347

Green Protocol for the Novel Synthesis of Thiochromeno[4,3- b]pyridine and Chromeno[4,3- b]pyridine Derivatives Utilizing a High-Pressure System

ACS Omega. 2021 Nov 30;6(49):34065-34074. doi: 10.1021/acsomega.1c05347. eCollection 2021 Dec 14.

Authors

Haider Behbehani¹, Kamal M Dawood², Fatemah A Aryan³, Hamada Mohamed Ibrahim^{1

4}

Affiliations

¹ Chemistry Department, Faculty of Science, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait.
² Chemistry Department, Faculty of Science, Cairo University, Giza 12613, Egypt.
³ College of Basic Education, Science Department, Public Authority of Applied Education and Training, P.O. Box 23167, Safat 13092, Kuwait.
⁴ Chemistry Department, Faculty of Science, Fayoum University, Fayoum 63514, Egypt.

Abstract

A suitable and effective Q-tube-assisted strategy for the synthesis of novel, unrivalled thiochromeno[4,3-b]pyridine and chromeno[4,3-b]pyridine derivatives has been sophisticated, which includes ammonium acetate-mediated cyclocondensation reactions between 3-oxo-2-arylhydrazonopropanals and heterobenzocyclic ketones such as thiochroman-4-one and chroman-4-one, respectively. The high-pressure Q-tube reactor was shown to be superior to conventional heating. Furthermore, this Q-tube reactor-assisted protocol is safe owing to facile pressing and sealing, a broad substrate scope, and simple work-up and purification processes, as well as being scalable and having a high atom economy. The proposed mechanistic route includes two sequential dehydrative stages. In this investigation, X-ray crystallographic analysis was performed to authenticate the targeted products.