Ruthenium-Catalyzed Para-Selective Oxidative Cross-Coupling of Arenes and Cycloalkanes
作者:Xiangyu Guo、Chao-Jun Li
DOI:10.1021/ol202081c
日期:2011.10.7
A novel, direct para-selective oxidativecross-coupling of benzene derivatives with cycloalkanes catalyzed by ruthenium was developed. A wide range of arenes bearing electron-withdrawing substituents was functionalized directly with simple cycloalkanes with high para-selectivity; arenes with electron-donating groups were mainly para-functionalized. Benzoic acid can be used directly.
Visible-light-mediated photoredox minisci C–H alkylation with alkyl boronic acids using molecular oxygen as an oxidant
作者:Jianyang Dong、Fuyang Yue、Hongjian Song、Yuxiu Liu、Qingmin Wang
DOI:10.1039/d0cc05946c
日期:——
report a protocol for direct visible-light-mediated Minisci C–H alkylation reactions of heteroarenes with alkyl boronic acids using molecular oxygen as the sole oxidant. This mild protocol uses an inexpensive, green oxidant; permits efficient functionalization of various N-heteroarenes with a broad range of primary and secondaryalkyl boronic acids; and is scalable to the gram level. We demonstrated the
Metal-Free Oxidative Decarbonylative Coupling of Aliphatic Aldehydes with Azaarenes: Successful Minisci-Type Alkylation of Various Heterocycles
作者:Ren-Jin Tang、Lei Kang、Luo Yang
DOI:10.1002/adsc.201500268
日期:2015.6.15
A metal‐free oxidative decarbonylative coupling of aliphaticaldehydes with various electron‐deficient heterocycles has been developed. This reaction is supposed to be realized via a Minisci‐type mechanism, based on the substrate scope, regioselectivity and radical trapping experiments. The ready availability of aliphaticaldehydes, metal‐free conditions and broad substrate scope should make this method
Regio- and Stereoselective Alkylation of Pyridine-<i>N</i>-oxides: Synthesis of Substituted Piperidines and Pyridines
作者:Deepak Kumar Barange、Magnus T. Johnson、Andrew G. Cairns、Roger Olsson、Fredrik Almqvist
DOI:10.1021/acs.orglett.6b02667
日期:2016.12.16
Regio- and stereoselective addition of alkyl Grignard reagents to pyridine-N-oxides gave C2-alkylated N-hydroxy-1,2,5,6-tetrahydropyridines and trans-2,3-disubstituted N-hydroxy-1,2,5,6-tetrahydropyridines in good to excellent yields. These intermediates were aromatized or alternatively reduced in one-pot methodologies for efficient syntheses of alkylpyridines or piperidines, respectively. These reactions
A metal-free deformylative Minisci-type reaction is disclosed by using aliphatic aldehydes as alkyl radical precursors. The reaction proceeds via a sequence of hydrogen atom abstraction (HAA) from aldehyde and decarbonylation under mild photochemical conditions. The transformation offers many advantages including good regioselectivity, broad substrate scope, and easy operation. The reaction is also