Palladium-Catalyzed Decarboxylative Couplings of 2-(2-Azaaryl)acetates with Aryl Halides and Triflates
作者:Rui Shang、Zhi-Wei Yang、Yan Wang、Song-Lin Zhang、Lei Liu
DOI:10.1021/ja107103b
日期:2010.10.20
Pd-catalyzed decarboxylative cross-couplings of 2-(2-azaaryl)acetates with arylhalides and triflates have been discovered. This reaction is potentially useful for the synthesis of some functionalized pyridines, quinolines, pyrazines, benzoxazoles, and benzothiazoles. Theoretical analysis shows that the nitrogen atom at the 2-position of the heteroaromatics directly coordinates to Pd(II) in the decarboxylation
Photocatalyzed
<i>ortho</i>
‐Alkylation of Pyridine
<i>N</i>
‐Oxides through Alkene Cleavage
作者:Wang Zhou、Tomoya Miura、Masahiro Murakami
DOI:10.1002/anie.201801305
日期:2018.4.23
A photocatalyzed reaction of pyridine N‐oxides with alkenes gives ortho‐alkylated pyridines with cleavage of the carbon–carbon double bond. Benzyl and secondary alkyl groups are incorporated at the ortho position of pyridines in one pot.
6-dialkylpyridines can be synthesized from simple symmetrical substrates by repeating such C–H alumination/C–C bondformation processes. Because of the high regioselectivity of the present C–H alumination and the subsequent C–C bondformation, this protocol may serve as a desirable method for the synthesis of nonsymmetrically-2,6-disubstituted pyridine derivatives.