Synthesis 2019; 51(16): 3127-3141
DOI: 10.1055/s-0037-1610707
paper
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Bisflavanol-Type Natural Products and Their Analogues­ via Self-Coupling of C8-Methylol Catechin Derivatives

Deng-Ming Huang
a   School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P. R. of China   Email: lihuijing@iccas.ac.cn   Email: ycwu@iccas.ac.cn
,
Hui-Jing Li*
a   School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P. R. of China   Email: lihuijing@iccas.ac.cn   Email: ycwu@iccas.ac.cn
,
Yan Zhao
a   School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P. R. of China   Email: lihuijing@iccas.ac.cn   Email: ycwu@iccas.ac.cn
,
a   School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P. R. of China   Email: lihuijing@iccas.ac.cn   Email: ycwu@iccas.ac.cn
b   Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, P. R. of China
› Author Affiliations
This work was supported by the National Natural Science Foundation of China (21672046 and 21372054), the Fundamental Research Funds for the Central Universities (HIT.NSRIF.201701), and the Foundation from Huancui District of Wehai City.
Further Information

Publication History

Received: 13 January 2019

Accepted after revision: 25 March 2019

Publication Date:
24 April 2019 (online)


Abstract

A highly efficient and regioselective self-coupling of C8-methylol catechin derivatives is developed for the synthesis of dimeric flavanol analogues under metal-free and mild conditions. Its applicability is showcased by the efficient synthesis of bisflavanol-type natural products bis-8,8′-catechinylmethane, bis-8,8′-epicatechinylmethane, talienbisflavan A, and oolonghomobisflavan A. The novel self-coupling mechanism sheds new light on the classical Friedel–Crafts alkylation mechanism in acid-catalyzed catechin–formaldehyde condensation.

Supporting Information