314734-18-4Relevant academic research and scientific papers
Design of N-spiro C2-symmetric chiral quaternary ammonium bromides as novel chiral phase-transfer catalysts: Synthesis and application to practical asymmetric synthesis of α-amino acids
Ooi, Takashi,Kameda, Minoru,Maruoka, Keiji
, p. 5139 - 5151 (2007/10/03)
A series of C2-symmetric chiral quaternary ammonium bromides 10 and 11 have been designed as a new, purely synthetic chiral phase-transfer catalyst, and readily prepared from commercially available optically pure 1,1′-bi-2-naphthol as a basic c
Design of new, chiral phase-transfer catalysts for practical, catalytic asymmetric synthesis
Maruoka, Keiji
, p. 95 - 99 (2007/10/03)
Structurally rigid, chiral spiro ammonium salts of type 1 derived from commercially available (S)-binaphthol have been designed as a new C2-symmetric chiral phase-transfer catalyst and successfully applied to the highly efficient, catalytic enantioselective alkylation of tert-butyl glycinate Schiff base under mild phase-transfer conditions to furnish a-alkyl-oc-amino acids and α,α-dialkyl-α-amino acids with excellent enantioselectivity. These ammonium salts have been also utilized for the in situ generation of chiral quaternary ammonium fluorides.
Facile synthesis of L-Dopa tert-butyl ester by catalytic enantioselective phase-transfer alkylation
Ooi,Kameda,Tannai,Maruoka
, p. 8339 - 8342 (2007/10/03)
Facile asymmetric synthesis of L-Dopa and related amino acid esters has been achieved by phase-transfer catalysis of the rationally designed C2-symmetric chiral quaternary ammonium salts 1. The 'scale-up' experiment performed with 5.00 g of tert-butyl glycinate-benzophenone Schiff base (2) represents the practical aspect of our approach. (C) 2000 Elsevier Science Ltd.
