Synthesis of Benzo-fused Heterocycles by Intramolecular α-Arylation of Ketone Enolate Anions
作者:Javier F. Guastavino、Roberto A. Rossi
DOI:10.1021/jo202012n
日期:2012.1.6
benzo-fused heterocycles in good to excellent yields is reported. The synthetic strategy involves the generation of a new intramolecular α-aryl ketone bond by the photostimulated SRN1 reaction of ketone enolate anions linked to a pendant haloarene as the key step. On the other hand, an intramolecular CAr–CAr coupling led to the formation of five- and six-member benzo-fused heterocycles (9H-carbazole
据报道,六元,七元,八元和九元苯并稠合的杂环可以两步合成,产率高到极好。合成策略涉及通过与末端卤代芳烃连接的酮烯酸酯阴离子的光刺激S RN 1反应生成新的分子内α-芳基酮键。另一方面,当竞争性形成芳香酰胺阴离子时,分子内C Ar –C Ar偶联导致五元和六元苯并稠合杂环(9 H-咔唑和菲啶)的形成。
Dual Catalysis in Domino<i>N</i>-Benzylation/Intramolecular C-H Arylation: Regio- and Chemoselective Synthesis of Annelated Nitrogen Heterocycles
作者:Joydev K. Laha、Neetu Dayal、Swati Singh、Rohan Bhimpuria
DOI:10.1002/ejoc.201402395
日期:2014.9
A general method has been developed for the synthesis of fused nitrogenheterocycles by using a domino N-benzylation/C–Harylation reaction sequence. The details and yields of the domino process were compared with those of the two-step literature protocol. Fused azaindoles, which are otherwise difficult to obtain, were synthesized by using this process. The unprecedented catalytic role of PPh3 in this