Synthesis of pyrano[3,2- c]quinolones and furo[3,2- c]quinolones via acid-catalyzed tandem reaction of 4-hydroxy-1-methylquinolin-2(1 H)-one and propargylic alcohols

Haiting Yin; Yunjun Wu; Xiaoxia Gu; Zhijun Feng; Meifang Wang; Dexiang Feng; Ming Wang; Ziyang Cheng; Shaoyin Wang

doi:10.1039/d2ra03416f

Synthesis of pyrano[3,2- c]quinolones and furo[3,2- c]quinolones via acid-catalyzed tandem reaction of 4-hydroxy-1-methylquinolin-2(1 H)-one and propargylic alcohols

RSC Adv. 2022 Jul 21;12(33):21066-21078. doi: 10.1039/d2ra03416f.

Authors

Haiting Yin¹, Yunjun Wu¹, Xiaoxia Gu¹, Zhijun Feng¹, Meifang Wang^{1

2}, Dexiang Feng¹, Ming Wang¹, Ziyang Cheng¹, Shaoyin Wang^{1

2}

Affiliations

¹ Department of Chemistry, Institute of Synthesis and Application of Medical Materials, Chunhui Scientific Research Interest Group, Wannan Medical College Wuhu 241002 China.
² The Key Laboratory of Antiinflammatory and Immune Medicine, Ministry of Education, Anhui Medical University Hefei 230032 China wsychem@163.com.

Abstract

Two acid-catalyzed tandem reactions between 4-hydroxy-1-methylquinolin-2(1H)-one and propargylic alcohols are described. Depending mainly on the propargylic alcohol used, these tandem reactions proceed via either a Friedel-Crafts-type allenylation followed by 6-endo-dig cyclization sequence to form pyrano[3,2-c]quinolones or a Friedel-Crafts-type alkylation and 5-exo-dig ring closure sequence to afford furo[3,2-c]quinolones in moderate-to-high yields. The pyrano[3,2-c]quinolones products could be further transformed to tetracyclic 4,9-dihydro-5H-cyclopenta[lmn]phenanthridin-5-one derivatives.