Enantioselective synthesis of α-halo-α-alkylmalonates via phase-transfer catalytic α-alkylation.
نویسندگان
چکیده
A new enantioselective synthetic method for α-halo-α-alkylmalonates is reported. α-Alkylation of diphenylmethyl tert-butyl α-halomalonates under phase-transfer catalytic conditions (solid KOH, toluene, -40 °C) in the presence of (S,S)-3,4,5-trifluorophenyl-NAS bromide (5 mol%) afforded diphenylmethyl tert-butyl α-halo-α-alkylmalonates in very high chemical yields (up to 99%) and optical yields (up to 93% ee).
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 12 9 شماره
صفحات -
تاریخ انتشار 2014