Copper-catalyzed cascade annulation between α-bromocarbonyls and biaryl or (Z)-arylvinylacetylenes enabling a direct synthesis of dibenzocycloheptanes and related compounds
作者:Danyang Lu、Yimei Wan、Lichun Kong、Gangguo Zhu
DOI:10.1039/c6cc07727g
日期:——
A copper-catalyzed cascade annulation of [gamma],[small delta]-unsaturated [small alpha]-bromocarbonyls with biaryl or (Z)-arylvinylacetylenes is presented, giving an expeditious access to dibenzocycloheptanes and relatedcompounds in moderate to high yields. It provides a...
Silver-Catalyzed Tandem C≡C Bond Hydroazidation/Radical Addition/Cyclization of Biphenyl Acetylene: One-Pot Synthesis of 6-Methyl Sulfonylated Phenanthridines
作者:Jiawei Tang、Paramasivam Sivaguru、Yongquan Ning、Giuseppe Zanoni、Xihe Bi
DOI:10.1021/acs.orglett.7b01771
日期:2017.8.4
silver-catalyzed tandem carbon–carbon triple bond hydroazidation, radical addition, and cyclization of biphenyl acetylene is described under mild conditions, leading to the formation of 6-methyl sulfonylated phenanthridines in good yields. In this novel cascade reaction, most of the atoms are incorporated into the product without cleavage of the C≡C bond. Mechanistic studies suggest the reaction should proceed
Palladium-Catalyzed Cycloisomerization of 2-Ethynylbiaryls to 9-Methylidene Fluorenes
作者:Hongyu Guo、Sheng Zhang、Xiujuan Feng、Xiaoqiang Yu、Yoshinori Yamamoto、Ming Bao
DOI:10.1021/acs.orglett.2c00534
日期:2022.4.15
presence of weak acid at low temperature to afford 9-methylidene fluorenes in satisfactory to high yields. This new type of cycloisomerization of 2-ethynylbiaryls is operationally simple and scalable and exhibits high functional-group tolerance. Various synthetically useful functional groups, such as halogen atoms, as well as formyl, acetyl, methoxycarbonyl, cyano, and nitro groups, remain intact during