Chromium(VI)-catalysed oxidations of alcohols and benzylic methylene groups by sodium percarbonate have been carried out in refluxing benzotrifluoride; comparisons with previous studies showed that this solvent is a valuable alternative to 1,2-dichloroethane for such reactions.
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The boiling point of BTF is 102 °C while DCE boils at 83 °C. Preliminary experiments using BTF as solvent have shown that reactions carried out at 83 or 102 °C lead to similar results.
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Selectivity represents the yield based on the amount of substrate consumed.
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Following a referee's remark regarding the recoverability of the solvent, preparative experiments were carried out using 8 mmol of indan-1-ol in 80ml of BTF. Some BTF (55–60ml) was thus recovered by distillation of the filtrate under atmospheric pressure. After complete evaporation of the solvent under reduced pressure, the residue was subjected to flash chromatography, eluting with EtOAc–light petroleum (bp 30–60 °C) (20/80).
