Tandem 6π-Azatriene Electrocyclization of Fused Amino-cyclopentenones: Synthesis of Functionalized Pyrrolo- and Indolo-quinoxalines
作者:Kapil Mohan Saini、Rakesh K. Saunthwal、Ankit Kumar、Akhilesh K. Verma
DOI:10.1021/acs.orglett.1c02782
日期:2021.10.1
A tandem 6π-azacyclization approach for the synthesis of diversified pyrrolo/indolo[1,2-a]quinoxalines from amino-cyclopentenones has been developed. The reaction proceeds through a trifluoroacetic-acid-mediated 6π-electrocyclization and concomitant opening of the cyclopentenone ring. The advantageous features of the developed chemistry include transition-metal-free conditions, operational simplicity
已经开发了一种用于从氨基环戊烯酮合成多样化吡咯并/吲哚[1,2- a ]喹喔啉的串联 6π-氮杂环化方法。该反应通过三氟乙酸介导的 6π-电环化和环戊烯酮环的伴随打开进行。所开发化学的优势特征包括无过渡金属条件、操作简单和广泛的底物范围。进一步的 X 射线晶体学研究证实了稠合杂环的指定结构。
On Water: Silver-Catalyzed Domino Approach for the Synthesis of Benzoxazine/Oxazine-Fused Isoquinolines and Naphthyridines from<i>o</i>-Alkynyl Aldehydes
作者:Akhilesh K. Verma、Deepak Choudhary、Rakesh K. Saunthwal、Vineeta Rustagi、Monika Patel、Rakesh K. Tiwari
DOI:10.1021/jo4009639
日期:2013.7.5
An operationally simple domino approach for the silver-catalyzed synthesis of oxazine/benzoxazine-fused isoquinolines 5a-q and naphthyridines 6a-v by the reaction of o-alkynyl aldehydes 3a-aa with amines having embedded nucleophiles 4a-d under mild reaction condition in water is described. The reaction shows selective C-N bond formation on the more electrophilic alkynyl carbon resulting in the formation of 6-endo-dig cyclized product. The competitive experiments show the viability of an intramolecular nucleo philic attack over an intermolecular attack of the external nucleophile. This methodology accommodates wide functional group variation, which proves to be useful for structural and biological assessment.