COMMUNICATIONS
Copper-Catalyzed Oxidative Ring Closure of ortho-Cyanoanilides
drous sodium sulfate, filtered and evaporated. Purification
of the crude products by column chromatography on silica
gel afforded the products as solids.
Acknowledgements
This project was supported by the “Lendꢀlet” Research
Scholarship of the Hungarian Academy of Sciences
(
LP2012-48/2012), and by TꢁT-10-1-2011-0245. The authors
also thank Prof. Tim Peelen for the proofreading of this
manuscript.
Scheme 5. Proposed mechanistic steps for the transforma-
tion.
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General Procedure
N-(2-Cyanophenyl)acetamide (1a) (80.1 mg, 0.500 mmol),
diaryliodonium salt (0.600 mmol, 1.2 equiv.) and copper(II)
triflate (18.08 mg; 0.050 mmol, 10 mol%) were added to a 4-
mL vial and then the system was charged with argon. Sol-
vent (1,2-dichloroethane or ethyl acetate, 1 mL) was added
under an argon atmosphere and the reaction mixture was
stirred at 758C for the appropriate time. Saturated sodium
hydrogen carbonate solution (10 mL) was added to the mix-
ture, the aqueous layer was extracted with dichloromethane
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4ꢄ10 mL) the combined organics were dried over anhy-
Adv. Synth. Catal. 0000, 000, 0 – 0
ꢃ 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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