difunctionalization at C5/C8 of imidazo[1,2-a]pyrazines has been developed using disulfides and Grignardreagents under cheap cobalt catalysis. This one-pot, two-step, three-component transformation is performed under mild conditions; various Grignardreagents (aryl and alkyl) and disulfides are tolerated. Mechanistic studies and control experiments demonstrate this reaction proceeded via an anionic intermediate
在廉价的钴催化下,使用二硫化物和格氏试剂开发了咪唑并[1,2 -a ]吡嗪在 C5/C8 的有效双官能化。这种一锅两步三组分转化是在温和的条件下进行的;可以耐受各种格氏试剂(芳基和烷基)和二硫化物。机理研究和控制实验表明该反应是通过阴离子中间体进行的。
Reactivity of Phenyllithium toward Bridgehead Nitrogen Heterocycles
作者:Alain Gueiffier、Henri Viols、Yves Blache、Olivier Chavignon、Jean Claude Teulade、Andr� Aumelas、Jean-Pierre Chapat
DOI:10.3987/com-93-6581
日期:——
The reactivity of phenyllithium toward some bridgehead nitrogen heterocycles was investigated. Imidazo[1,2-a]pyridine gave the substitution, while other series gave addition reactions. In addition, the ring opening derivative was obtained in imidazo[1,2-c]quinazoline series.
Catalytic Arylation of a CH Bond in Pyridine and Related Six-Membered N-Heteroarenes Using Organozinc Reagents
作者:Isao Hyodo、Mamoru Tobisu、Naoto Chatani
DOI:10.1002/asia.201100971
日期:2012.6
Despite significant advances in the catalytic direct arylation of heteroarenes, the application of this reaction to pyridines has been met with limited success. An oxidative nucleophilic arylation strategy has been developed to overcome this problem. Pyridine, pyrazine, quinolone, and related electron‐deficient N‐heteroarenes can be arylated at the most electrophilic site using the developed nickel‐catalyzed