The first example of a homogeneous gold(III)-catalysed epoxidation of aromatic alkenes at room temperature using sodium chlorite as the stoichiometric oxidant in a homogeneous trisolvent system of 2-methoxyethanol/acetonitrile/water (volume ratio: 1/3/1) is reported. A radical-trapping experiment suggested that the reaction might proceed via a radical pathway.
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GengX. -L., WangZ., LiX.-Q., and ZhangC., J. Org. Chem., 2005, 70, 9610.
15.
Other oxidants such as H2O2, Oxone, NaOCl, and PhIO did not give epoxidation product, only trace amount of C-C double bond cleavage products were detected.
16.
See Supplementary Data for details.
17.
For the preparation of chloro(triphenylphosphine)gold(I), see: BurgessK., JohnsonB.F.G., LewisJ., and RaithbyP.R.J. Chem. Soc., Dalton Trans., 1983, 1661.
18.
For the preparation of dichloro(pyridine-2-carboxylato)gold(III), see: (a) DarA., MossK., CottrillS. M., ParishR.V., McAuliffeC.A., PritchardR.G., BeagleyB., and SandbankJ., J. Chem. Soc., Dalton Trans., 1992, 1907; For applications of dichloro(pyridine-2-carboxylato)gold(III), see: (b) S. Wang and L. Zhang, J. Am. Chem. Soc., 2006, 128, 8414; (c) S. Wang and L. Zhang, J. Am. Chem. Soc., 2006, 128, 14274; (d) A.S.K. Hashimi, J.P. Weyrauch, M. Rudolph and E. Kurpejovic, Angew. Chem., Int. Ed., 2004, 43, 6545.
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OudeyerS., LéonelE., PaugamJ.P., and NédélecJ. -Y., Synthesis, 2004, 3, 389.
