A rate enhancement of phase transfer catalyzed conjugate additions was accomplished using a catalytic amount of CsCl. The utility of this method was demonstrated in the asymmetric synthesis of glutamic acid derivatives by using a chiral phase transfer catalyst.

An enantioselective organocatalytic, one-pot synthesis of pyrrolidine, hexahydropyrrolizine, and octahydroindolizine core structures was realized starting from readily available glycine esters by combination with several different organocatalytic reactions.

An asymmetric synthesis of cyclic amino acids having piperidine and azepane core structures was realized starting from readily available glycine and alanine esters by combination of phase-transfer catalyzed asymmetric alkylation and subsequent reductive amination. Some of these key intermediates were successfully transformed to natural alkaloid dihydropinidine and N-methyl-D-aspartate (NMDA) antagonist Selfotel.Scheme 1 Asymmetric synthesis of cyclic amino acids.

An asymmetric synthesis of cyclic amino acids having piperidine and azepane core structures was realized starting from readily available glycine and alanine esters by combination of phase-transfer catalyzed asymmetric alkylation and subsequent reductive amination.

Aminocarboxylic acids (hydrazinocarboxylic acids) and esters P 0270Rate Enhancement of Phase Transfer Catalyzed Conjugate Additions by CsCl.-The reagent remarkably accelerates addition of amino acid derivatives to acrylates and enhances the rate of asymmetric reaction without affecting the enantioselectivity.-(KANO, T.; KUMANO, T.; MARUOKA*, K.; Org. Lett. 11 (2009Lett. 11 ( ) 9, 2023Lett. 11 ( -2025 Dep. Chem., Grad. Sch. Sci., Kyoto Univ., Sakyo, Kyoto 606, Japan; Eng.) -Jannicke 36-051