Enantioselective Alkylation Using Optically Active Phase Transfer Catalyst
نویسندگان
چکیده
منابع مشابه
Enantioselective Decarboxylative Alkylation Reactions: Catalyst
α-Quaternary ketones are accessed through novel enantioselective alkylations of allyl and propargyl electrophiles by unstabilized prochiral enolate nucleophiles in the presence of palladium complexes with various phosphinooxazoline (PHOX) ligands. Excellent yields and high enantiomeric excesses are obtained from three classes of enolate precursors: enol carbonates, enol silanes, and racemic β-k...
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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 ...
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ژورنال
عنوان ژورنال: Bulletin of the Chemical Society of Japan
سال: 1979
ISSN: 0009-2673,1348-0634
DOI: 10.1246/bcsj.52.3119