Radical Benzylation of Quinones via C–H Abstraction
作者:Jordan D. Galloway、Duy N. Mai、Ryan D. Baxter
DOI:10.1021/acs.joc.9b01004
日期:2019.9.20
Herein we report the development of radical benzylation reactions of quinones using Selectfluor and catalytic Ag(I) initiators. The reaction is believed to proceed via a C–H abstraction mechanism after Ag(I)-mediated reduction of Selectfluor. This reaction occurs under mild conditions and is effective for a variety of quinones and radical precursors bearing primary benzylic carbons. The use of preformed
本文中,我们报道了使用Selectfluor和催化Ag(I)引发剂对醌进行的自由基苄基化反应的发展情况。在Ag(I)介导的Selectfluor还原后,该反应被认为是通过C–H抽象机制进行的。该反应在温和的条件下发生,并且对于各种带有伯苄基碳的醌和自由基前体是有效的。事实证明,使用预制的Ag(4-OMePy)2 NO 3作为催化剂,可通过减少Selectfluor可利用的不需要的降解途径来有效提高反应效率。
Metal-, Photocatalyst-, and Light-Free, Late-Stage C–H Alkylation of Heteroarenes and 1,4-Quinones Using Carboxylic Acids
作者:Daniel R. Sutherland、Marcos Veguillas、Conor L. Oates、Ai-Lan Lee
DOI:10.1021/acs.orglett.8b02988
日期:2018.11.2
Contrary to the accepted convention, this work shows that Minisci-type C–Halkylation does not require any metal, photocatalyst, light, or prefunctionalization of the readily available and inexpensive carboxylic acids to proceed well under mild conditions. These mild conditions can be utilized for late-stage alkylations of complex molecules, including pharmaceutical compounds and light-sensitive compounds
Copper-Catalyzed Regioselective Cross-Dehydrogenative Coupling of Coumarins with Benzylic C<sub>sp3</sub>-H Bonds
作者:Shi-Liu Zhou、Li-Na Guo、Xin-Hua Duan
DOI:10.1002/ejoc.201403068
日期:2014.12
A new copper-catalyzed regioselective cross-dehydrogenativecoupling of coumarins with benzylic Csp3–H bonds has been developed. This reaction provides direct access to a wide range of 3-benzylcoumarins in moderate to good yields. The protocol was also extended successfully to other heterocyclic compounds, such as quinolinones.
Iron-catalyzed regioselective alkylation of 1,4-quinones and coumarins with functionalized alkyl bromides
作者:Dengke Li、Xianfu Shen
DOI:10.1039/c9ob02289a
日期:——
A simple and efficient Fe-catalyzed regioselectivealkylation of 1,4-quinones and coumarins, using functionalized alkyl bromides as alkylating reagents, has been developed. The reaction proceeds under mild conditions with the addition of alkyl bromides to a wide range of 1,4-quinone and coumarin derivatives with a broad substrate scope and wide functional group tolerance to provide the products in