Rh(III)-Catalyzed [3 + 2] Spirocyclization of 2H-Imidazoles with 1,3-Diynes for the Synthesis of Spiro-[imidazole-indene] Derivatives
摘要:
An effective strategy to synthesize spirocyclic compounds, [imidazole-4,1'-indene], has been efficaciously developed relied on Rh(III)-catalyzed [3 + 2] spirocyclization of 2H-imidazoles and 1,3-diynes with excellent chemselectivity and regioselectivity. This protocol shows a straightforward way to construct the versatile spirocyclic compounds with wide functional group compatibility, high atom economy, and diverse functionalization of products.
Palladium(0)-Catalyzed, Copper(I)-Mediated Coupling of Boronic Acids with Cyclic Thioamides. Selective Carbon−Carbon Bond Formation for the Functionalization of Heterocycles<sup>†</sup>
作者:Hana Prokopcová、C. Oliver Kappe
DOI:10.1021/jo070408f
日期:2007.6.1
Employing controlled microwaveirradiation at 100 °C, most cross-couplings can be completed within 2 h and proceed in high yields. An advantage of using thioamides as starting materials is the fact that the system can be tuned to an alternative carbon−sulfur cross-coupling pathway by changing to stoichiometric copper(II) under oxidative conditions. Both types of thioamide cross-couplings are orthogonal to
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-
Desulfitative Carbon–Carbon Cross-Coupling of Thioamide Fragments with Boronic Acids
作者:Hana Prokopcová、C. Oliver Kappe
DOI:10.1002/adsc.200600566
日期:2007.2.5
general carbon–carbon cross-coupling reaction between cyclic thioamides and boronic acids is described. The reaction is catalytic in palladium(0) and requires stoichiometric amounts of a copper(I) carboxylate as metal cofactor. The mode of cross-coupling in the reaction of cyclic thioamides with boronic acids is easily tunable between carbon–carbon and carbon–sulfur cross-coupling. While the catalytic