Abstract
Benzylic C-H bonds next to electron rich aromatic rings are susceptible to 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) promoted functionalization. In this work benzylic carbocations formed in this manner are trapped by a pendant carboxylic acid to form a lactone. Indole-3-butyric acids are especially good substrates for the reaction. The lactonization functions well with catalytic amounts of DDQ combined with MnO2 as the stoichiometric oxidant. This cyclization proceeds with a number of indole-3-butyric acids, and yields were generally good as long as the indole was electron rich and free of bulky substituents near the reacting benzylic carbon. Indole-3-butyric acids functionalized with electron withdrawing groups tend to give more moderate yields. Other aromatic substrates also participate as long as the aromatic ring is functionalized with electron donating groups.
Original language | English (US) |
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Pages (from-to) | 24207-24211 |
Number of pages | 5 |
Journal | RSC Advances |
Volume | 14 |
Issue number | 33 |
DOIs | |
State | Published - Aug 2 2024 |
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering