ChemInform Abstract: Rh-Catalyzed Oxidative Coupling Between Primary and Secondary Benzamides and Alkynes: Synthesis of Polycyclic Amides.

Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China 116023.
The Journal of Organic Chemistry (Impact Factor: 4.72). 10/2010; 75(21):7487-90. DOI: 10.1021/jo101596d
Source: PubMed


A methodology for the high yield and facile synthesis of isoquinolones from benzamides and alkynes via the oxidative ortho C-H activation of benzamides has been developed. Ag(2)CO(3) proved to be an optimal oxidant when MeCN was used as a solvent, and [RhCp*Cl(2)](2) was utilized as an efficient catalyst. Both N-alkyl and N-aryl secondary benzamides can be applied as effective substrates. Furthermore, primary benzamides react with two alkyne units, leading to tricyclic products via double C-H activation and oxidative coupling. The reactivity of the structurally related 1-hydroxyisoquinoline was also demonstrated, where both N- and O-containing rhodacyclic intermediates can be generated, leading to the construction of different O- or N-containing heterocycles.

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