ChemInform Abstract: Organocatalyzed Isomerization of α‐Substituted Alkynoates into Trisubstituted Allenoates by Dynamic Kinetic Resolution.

Abstract

Organocatalyzed Isomerization of α-Substituted Alkynoates into Trisubstituted Allenoates by Dynamic Kinetic Resolution. -The isomerization of alkynoates is smoothly catalyzed by a bicyclic guanidine-diamine catalyst to afford the trisubstituted allenoates (II) in high enantioselectivities (up to 94% e.e.). The reaction proceeds with epimerization of the starting alkynoate and, thus, allows for higher chemical yields as compared to previously described isomerization reactions. Additionally, the α-substituent at the allenoate suppresses the reverse isomerization. -(INOKUMA, T.; FURUKAWA, M.; SUZUKI, Y.; KIMACHI, T.; KOBAYASHI, Y.; TAKEMOTO*, Y.; ChemCatChem 4 (2012) 7, 983-985, http://dx.doi.org/10.1002/cctc.201200065 ; Grad. Sch. Pharm. Sci., Kyoto Univ., Sakyo, Kyoto 606, Japan; Eng.) -Mischke 42-063