Synlett 2015; 26(13): 1890-1894
DOI: 10.1055/s-0034-1378841
letter
© Georg Thieme Verlag Stuttgart · New York

Facile Access to Benzothiophenes through Metal-Free Iodine-­Catalyzed Intermolecular Cyclization of Thiophenols and Alkynes

Kelu Yan
a   Shandong Province Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal Univesity, Jingxuan Road, Qufu 273165, Shandong, P. R. of China
,
Daoshan Yang*
a   Shandong Province Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal Univesity, Jingxuan Road, Qufu 273165, Shandong, P. R. of China
b   Jining Functional Materials and Surface Treatment Technology R & D Center, Southern Shandong Academy of Engineering Technology, ­Jining 272000, Shandong, P. R. of China   Email: yangdaoshan@tsinghua.org.cn   Email: huawang_qfnu@126.com
,
Mengqi Zhang
a   Shandong Province Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal Univesity, Jingxuan Road, Qufu 273165, Shandong, P. R. of China
,
Wei Wei
a   Shandong Province Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal Univesity, Jingxuan Road, Qufu 273165, Shandong, P. R. of China
,
Yao Liu
a   Shandong Province Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal Univesity, Jingxuan Road, Qufu 273165, Shandong, P. R. of China
,
Laijin Tian
a   Shandong Province Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal Univesity, Jingxuan Road, Qufu 273165, Shandong, P. R. of China
,
Hua Wang*
a   Shandong Province Key Laboratory of Life-Organic Analysis, School of Chemistry and Chemical Engineering, Qufu Normal Univesity, Jingxuan Road, Qufu 273165, Shandong, P. R. of China
b   Jining Functional Materials and Surface Treatment Technology R & D Center, Southern Shandong Academy of Engineering Technology, ­Jining 272000, Shandong, P. R. of China   Email: yangdaoshan@tsinghua.org.cn   Email: huawang_qfnu@126.com
› Author Affiliations
Further Information

Publication History

Received: 04 April 2015

Accepted after revision: 10 May 2015

Publication Date:
14 July 2015 (online)


Abstract

A novel iodine-catalyzed method for the synthesis of benzothiophene derivatives through cascade reactions of substituted thiophenols with alkynes has been demonstrated under metal- and solvent-free conditions. The present protocol uses inexpensive and environmentally friendly molecular iodine as the catalyst, and the corresponding products are obtained in moderate to excellent yields. Such an efficient, economical, and green transformation should provide an attractive approach to various benzothiophenes within organic and medicinal chemistry.

 
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