1403336-56-0Relevant articles and documents
Friedel-Crafts alkylations of electron-rich aromatics with 3-hydroxy-2-oxindoles: Scope and limitations
Kinthada, Lakshmana K.,Ghosh, Santanu,Babu, K. Naresh,Sharique, Mohd.,Biswas, Soumava,Bisai, Alakesh
, p. 8152 - 8173 (2015/01/08)
A Lewis acid-catalyzed nucleophilic addition of electron rich aromatics with 3-hydroxy-2-oxindoles 5 was developed. The reaction is believed to proceed through the 2H-indol-2-one ring system 9, which eventually reacts with various electron-rich aromatics to afford a variety of 2-oxindoles with an all-carbon quaternary center at the pseudobenzylic position (4, 8, 13, and 16) in high yields. The methodology provides an expeditious route to the tetracyclic core (3) of diazonamide (1), and azonazine (2) as well as the tricyclic core of asperazine (6a), idiospermuline (6b), and calycosidine (6c) viz. C(3a)-arylpyrroloindolines 7 having an all-carbon quaternary center on further synthetic elaboration.
Lewis acid-catalyzed Friedel-Crafts alkylations of 3-hydroxy-2-oxindole: An efficient approach to the core structure of azonazine
Ghosh, Santanu,Kinthada, Lakshmana K.,Bhunia, Subhajit,Bisai, Alakesh
supporting information, p. 10132 - 10134 (2012/11/13)
A Lewis acid catalyzed Friedel-Crafts reaction of electron rich aromatics with 3-alkyl-3-hydroxy-2-oxindole (5) has been developed. The methodology provides a straightforward access to the core of azonazine (2) sharing an all-carbon quaternary stereocenter at the tetracyclic ring junction. The Royal Society of Chemistry 2012.