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[6] a) S. Nagayama, S. Kobayashi, Angew. Chem. 2000, 112, 578 –
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ionic liquids form ionic-liquid phases on the surface of silica gel
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[11] See the Supporting Information.
[12] Other examples are shown in the Supporting Information.
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[15] The product was obtained in 28% yield with 66% ee under the
following conditions: 4 (6.5 mol%), [HBIm]NTf2 (50 wt%, 20
mol%), Silica-Sc-IL (0.24 mmolgÀ1, 5 mol%), H2O, 35 8C, 24 h.
ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 7217 –7220