Paper
Organic & Biomolecular Chemistry
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Experimental
General procedure for the NHC-catalyzed oxidative cyclization
reactions of 2-alkenylbenzaldehydes
To a solution of the substrate 1, 3, 6, or 8 (0.100 mmol,
1 equiv.) in toluene (0.5 mL, 0.2 M) was added 2-mesityl-
2,5,6,7-tetrahydropyrrolo[2,1-c][1,2,4]triazol-4-ium chloride (A)
(5.4 mg, 0.020 mmol, 20 mol%) and NEt3 (6 µL, 0.040 mmol,
40 mol%). The resulting mixture was stirred at the reported
temperature for the reported time under aerobic conditions.
After the reaction was completed, the reaction mixture was
cooled to room temperature, diluted with distilled water,
extracted with CH2Cl2 (three times), dried over MgSO4, and
concentrate in vacuo. The residue was purified by column
chromatography on silica gel to give the corresponding
product.
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Acknowledgements
This work was supported by both Basic Science Research
Program and Nano·Material Technology Department Program
through the National Research Foundation of Korea (NRF)
funded by the Ministry of Education, Science and
Technology (no. 2010-0007737, 2012R1A1A2041471, and
2012M3A7B4049654).
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2392 | Org. Biomol. Chem., 2014, 12, 2388–2393
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