Redox Amination of Indoline with Aldehyde
COMMUNICATION
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and synthetic applications are underway in our laboratory.
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Experimental Section
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[8] For the optimization of this novel amination, see the Supporting In-
formation.
Representative procedure (3a): To
a
solution of benzaldehyde
(0.5 mmol), indoline (1.0 mmol) in toluene (2 mL) was added PhCOOH
(0.1 mmol) and 4 ꢁ MS (20 mg) under nitrogen atmosphere. The mixture
was stirred at room temperature for 0.1 h and then heated at 1258C for
another 18 h. After the completion of the reaction, the solvent was
evaporated off and the crude mixture was purified by flash column chro-
matography to give the product 3a in 76% yield.
Acknowledgements
We thank the National Natural Science Foundation of China (No.
21025207) and 20975092 for the financial support.
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Keywords: hydride transfer · hydrogen bonds · indoles ·
redox amination · redox chemistry
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[11] See Table S1 in the Supporting Information.
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Received: July 6, 2010
Published online: November 4, 2010
Chem. Eur. J. 2010, 16, 13352 – 13355
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