presents the first example of the Pd-catalyzed cascade reactions of 5-oxohexanenitrile with arylboronicacids, affording important synthon 2-methylpyridines that can be further translated through C(sp3)-H functionalization to construct pyridine derivatives. Furthermore, this chemistry allows 5-oxo-5-arylpentanenitrile to react with arylboronicacids to provide unsymmetrical 2,6-diarylpyridines. This protocol
Direct C(sp<sup>3</sup>)–H Cross Coupling Enabled by Catalytic Generation of Chlorine Radicals
作者:Benjamin J. Shields、Abigail G. Doyle
DOI:10.1021/jacs.6b08397
日期:2016.10.5
Here we report the development of a C(sp3)-H cross-coupling platform enabled by the catalytic generation of chlorine radicals by nickel and photoredox catalysis. Aryl chlorides serve as both cross-coupling partners and the chlorine radical source for the α-oxy C(sp3)-H arylation of cyclic and acyclic ethers. Mechanistic studies suggest that photolysis of a Ni(III) aryl chloride intermediate, generated
Aryl substituted pyridines, pyrimidines, pyrazines and triazines and the use thereof
申请人:——
公开号:US20020040025A1
公开(公告)日:2002-04-04
This invention relates aryl substituted pyridines, pyrimidines, pyrazines and triazines of Formula I:
1
or a pharmaceutically acceptable salt, prodrug or solvate thereof, wherein A
1
, A
2
, A
3
, R
1
-R
4
, X and Y are set in the specification. The invention is also directed to the use of compounds of Formula I for the treatment of neuronal damage following global and focal ischemia, for the treatment or prevention of neurodegenerative conditions such as amyotrophic lateral sclerosis (ALS), and for the treatment, prevention or amelioration of both acute or chronic pain, as antitinnitus agents, as anticonvulsants, and as antimanic depressants, as local anesthetics, as antiarrhythmics and for the treatment or prevention of diabetic neuropathy.
A process for making certain 6-aryl-2-methyl-pyridines, which are useful intermediates in the preparation of biologically active compounds, comprises
(a) subjecting a ketal of 1-hydroxy-1-aryl-5-hexanone to a Jones oxidation to yield a 1-aryl-1,5-hexanedione; or treating the 1-aryl-1-hydroxy-5-ketal-hexane with manganese dioxide in solvent to yield a ketone; and
(b) reacting the 1-aryl-1,5-hexanedione or the ketone from (a) with excess hydroxylamine hydrochloride in polar solvent at a temperature of from 50°C to 100°C.