Acid-catalyzed reactions of 3-hydroxy-2-oxindoles with electron-rich substrates: synthesis of 2-oxindoles with all-carbon quaternary center.
نویسندگان
چکیده
A Lewis acid catalyzed reaction of in situ generated 2H-indol-2-one () 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.
منابع مشابه
Friedel-Crafts alkylations of electron-rich aromatics with 3-hydroxy-2-oxindoles: scope and limitations.
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 ...
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 11 40 شماره
صفحات -
تاریخ انتشار 2013