the visible light induced simple copper(II) chloride catalyzedoxidation of diarylacetylenes to α-diketones by molecular oxygen at roomtemperature. The in situ generated copper(II)-superoxo complex is a light-absorbing species that oxidizes inert diarylacetylenes to α-diketones. In contrast to reported photochemical processes, the current oxidation protocol does not require any exogenous photocatalyst
Ruthenium(II)-Catalyzed Regioselective [3 + 2] Spiroannulation of 2<i>H</i>-Imidazoles with 2-Alkynoates
作者:Zhenyu Song、Zi Yang、Pu Wang、Zhaojiang Shi、Tingfang Li、Xiuling Cui
DOI:10.1021/acs.orglett.0c02024
日期:2020.8.21
The C═N double bond of 2H-imidazole has been employed as a C-electrophile for the ruthenium(II)-catalyzed [3 + 2] spiroannulation reaction of 4-phenyl-2H-imidazoles and 2-alkynoates to synthesize spiroimidazole-4,1′-indenes. This strategy features high regioselectivity, broad functional group tolerance, and use of ruthenium as a catalyst, providing a new method to synthesize spirocycles with potential
Synthesis of α-Ketone-isoquinoline Derivatives via Tandem Ruthenium(II)-Catalyzed C–H Activation and Annulation
作者:Xiao-Lin Wu、Lin Dong
DOI:10.1021/acs.orglett.8b02759
日期:2018.11.16
A new ruthenium(II)-catalyzed tandem C–Hactivation/cyclization/hydrolysis cascade process of 2H-imidazoles and alkynes for facile and regioselective access to α-ketone-isoquinolines has been successfully developed. 2H-Imidazole as the novel traceless directing group has been well applied in this paper. The protocol features mild reaction conditions and easily accessible starting materials, and α-
A sequential one-pot approach to 1,2,4,5-tetrasubstituted-2H-imidazole synthesis from disubstituted alkynes
作者:Siva Senthil Kumar Boominathan、Chung-Yu Chen、Po-Jui Huang、Ruei-Jhih Hou、Jeh-Jeng Wang
DOI:10.1039/c5nj00959f
日期:——
A sequential one-pot approach to the tetrasubstituted 2H-imidazole scaffolds has been developed from disubstitutedalkynes and structurally diverse ketones. The reaction proceeds via a diketo intermediate generated from internal alkynes followed by the addition of ammonium acetate and a suitable ketone, affording a diverse range of 2H-imidazoles. Using air-moisture stable reaction conditions and inexpensive