Dearomative ring expansion of thiophenes by bicyclobutane insertion

• 成果类型: Article
• 署名作者: Wang, Huamin; Shao, Huiling; Das, Ankita; Dutta, Subhabrata; Chan, Hok Tsun; Daniliuc, Constantin; Houk, K. N.; Glorius, Frank
• 署名单位: University of California System; University of California Los Angeles
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-12100
• DOI: 10.1126/science.adh9737
• 发表日期: 2023-07-07
• 页码: 75-81
• 关键词: catalysis; photochemistry; complexes; STATES; mild

摘要

Skeletal ring enlargement is gaining renewed interest in synthetic chemistry and has recently focused on insertion of one or two atoms. Strategies for heterocyclic expansion through small-ring insertion remain elusive, although they would lead to the efficient formation of bicyclic products. Here, we report a photoinduced dearomative ring enlargement of thiophenes by insertion of bicyclo[1.1.0]butanes to produce eight-membered bicyclic rings under mild conditions. The synthetic value, broad functional-group compatibility, and excellent chemo- and regioselectivity were demonstrated by scope evaluation and product derivatization. Experimental and computational studies point toward a photoredox-induced radical pathway.