1463045-74-0Relevant academic research and scientific papers
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.
Acid-catalyzed reactions of 3-hydroxy-2-oxindoles with electron-rich substrates: Synthesis of 2-oxindoles with all-carbon quaternary center
Kinthada, Lakshmana K.,Ghosh, Santanu,De, Subhadip,Bhunia, Subhajit,Dey, Dhananjay,Bisai, Alakesh
, p. 6984 - 6993 (2013/10/08)
A Lewis acid catalyzed reaction of in situ generated 2H-indol-2-one (9) with various 2π and other electron-rich substrates has been developed. A variety of electron-rich substrates such as allyl/methallyltrimethylsilane, phenylacetylene, styrenes, acetophenone, and indoles have been used. The methodology provides a straightforward approach for the synthesis of 2-oxindoles with an all-carbon quaternary center at the pseudobenzylic position.
