title: Copper-catalyzed annulation of heteroaromatic β-halo-α,β-unsaturated carboxylic acids with alkynes for the synthesis of indolo[2,3-c]pyrane-1-ones and thieno[2,3-c]pyrane-7-ones.
abstract: The annulation of heteroaromatic β-halo-α,β-unsaturated carboxylic acids with alkynes proceeds efficiently in the presence of Cu(OAc)2·H2O as a catalyst to afford the corresponding indolo[2,3-c]pyrane-1-ones and thieno[2,3-c]pyrane-7-ones in moderate to good yields. This strategy offers a simple and efficient route for the synthesis of indolo[2,3-c]pyrane-1-ones and thieno[2,3-c]pyrane-7-ones with good tolerance to a variety of functional groups from easily available heteroaromatic β-halo-α,β-unsaturated carboxylic acids.
authors.affiliation: Shanghai Center for Systems Biomedicine, Ministry of Education Key Laboratory of Systems Biomedicine, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China. xunxiang_guo@sjtu.edu.cn.
authors.forename: Da-Wei
authors.initials: DW
authors.lastname: Gu
authors.forename: Xun-Xiang
authors.initials: XX
authors.lastname: Guo
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000480:Alkynes; D002264:Carboxylic Acids; D006841:Hydrocarbons, Aromatic; D007211:Indoles; D003300:Copper