919513-66-9Relevant academic research and scientific papers
Aryloxide-Facilitated Catalyst Turnover in Enantioselective α,β-Unsaturated Acyl Ammonium Catalysis
Matviitsuk, Anastassia,Greenhalgh, Mark D.,Antúnez, Diego-Javier Barrios,Slawin, Alexandra M. Z.,Smith, Andrew D.
, p. 12282 - 12287 (2017)
A new general concept for α,β-unsaturated acyl ammonium catalysis is reported that uses p-nitrophenoxide release from an α,β-unsaturated p-nitrophenyl ester substrate to facilitate catalyst turnover. This method was used for the enantioselective isothiourea-catalyzed Michael addition of nitroalkanes to α,β-unsaturated p-nitrophenyl esters in generally good yield and with excellent enantioselectivity (27 examples, up to 79 % yield, 99:1 er). Mechanistic studies identified rapid and reversible catalyst acylation by the α,β-unsaturated p-nitrophenyl ester, and a recently reported variable-time normalization kinetic analysis method was used to delineate the complex reaction kinetics.
Highly enantioselective organocatalytic Michael addition of nitroalkanes to 4-oxo-enoates
Lu, Hai-Hua,Wang, Xu-Fan,Yao, Chang-Jiang,Zhang, Jian-Ming,Wu, Hong,Xiao, Wen-Jing
supporting information; scheme or table, p. 4251 - 4253 (2011/03/19)
A useful Michael addition reaction using nitroalkanes as the nucleophile and 4-oxo-enoates as the Michael acceptor has been disclosed, and the reaction allows expedient access to functionalized chiral γ-keto esters in high yields and excellent enantioselectivities (up to 98% ee), with a low catalyst loading.
