Design of new, chiral phase-transfer catalysts for practical, catalytic asymmetric synthesis
作者:Keiji Maruoka
DOI:10.1016/s0022-1139(01)00472-9
日期:2001.11
Structurally rigid, chiral spiro ammonium salts of type 1 derived from commercially available (S)-binaphthol have been designed as a new C2-symmetricchiralphase-transfercatalyst and successfully applied to the highly efficient, catalytic enantioselective alkylation of tert-butyl glycinate Schiff base under mild phase-transfer conditions to furnish α-alkyl-α-amino acids and α,α-dialkyl-α-amino acids with excellent
Distinct Advantage of the in Situ Generation of Quaternary Ammonium Fluorides under Phase-Transfer Conditions toward Catalytic Asymmetric Synthesis
作者:Takashi Ooi、Kanae Doda、Keiji Maruoka
DOI:10.1021/ol000382d
日期:2001.5.1
[structure in text] Quaternary ammonium fluorides were found to be efficiently generated in situ from the corresponding ammonium hydrogensulfates by treatment with commercially available potassiumfluoridedihydrate (KF.2H(2)O) in THF and directly used as a fluoridesource for the generation of carbon nucleophiles from organosilicon compounds. This method can be successfully applied to the preparation