UPDATES
ness (CTQ2013-46970-P) and the University of the Basque
Country (UFI QOSYC 11/12). G.U thanks the University of
the Basque Country for a postdoctoral scholarship. Finally,
technical and human support provided by SGIker of UPV/
EHU is gratefully acknowledged.
glycol 400 as solvent facilitates catalyst–product sepa-
ration.
Experimental Section
General Information
References
Commercially available reagents were used throughout
without purification unless otherwise stated. 1H and
13C NMR spectra were recorded on a Bruker AC-300 instru-
ment (300 MHz for 1H and 75.4 MHz for 13C) at 208C.
Chemical shifts (d) are given in ppm downfield from Me4Si
and are referenced as internal standard to the residual sol-
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1
vent (unless indicated) CDCl3 (d=7.26 for H and d=77.00
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General Procedure for the Aerobic Cleavage of
Benzyl Ethers in the Presence of VO(acac)2 and
Methyl 3,5-Bis[(1H-1,2,4-triazol-1-yl)methyl]benzoate
L
A round-bottom flask equipped with a magnetic stirrer bar
was charged with ether
1 (1 mmol), NaOAc (8.0 mg,
0.1 mmol), VO(acac)2 (20 mL of a 5ꢃ10ꢀ6 M solution in
PEG-400, 10ꢀ7 mmol), L (20 mL of a 5ꢃ10ꢀ6 M solution in
PEG-400, 10ꢀ7 mmol) and PEG 400 (1 mL) at room temper-
ature. The system was purged with molecular oxygen, and
an oxygen-filled balloon (1–1.2 atm) was connected. The
mixture was heated at 1208C under stirring for 48 h. The re-
1
action outcome was monitored by H NMR. Upon comple-
tion, the mixture was cooled to room temperature and HCl
0.5M (10 mL) was added. The acidified mixture was re-
fluxed for 5 h, and after cooling, water was added (30 mL
aprox.). The resulting solution was extracted with Et2O (4ꢃ
6 mL) and the combined organic layers were washed with
brine (1ꢃ5 mL), dried over anhydrous Na2SO4 and evapo-
rated under vacuum to give a residue which was purified by
flash column chromatography using hexane:ethyl acetate as
eluent (see the Supporting Information).
Acknowledgements
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This research was supported by the Basque Government (IT-
774-13), the Spanish Ministry of Economy and Competitive-
Adv. Synth. Catal. 0000, 000, 0 – 0
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ꢁ 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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