An organocatalytic asymmetric Michaeladdition of ketones to alkylidenemalonates has been developed. In the presence of 20 mol % of urea 1a or N-(pyrrolidin-2-ylmethyl)trifluoromethanesulfonamide 1j, the reactions of ketones with alkylidenemalonates afford the desired Michael adducts in moderate to good yields with good to high enantioselectivities under mild conditions.
Badger et al., Journal of the Chemical Society, 1948, p. 2011,2013 Anm.
作者:Badger et al.
DOI:——
日期:——
Betancort, Juan M.; Sakthivel, Kandasamy; Thayumanavan, Rajeswari, Synthesis, 2004, # 9, p. 1509 - 1521
作者:Betancort, Juan M.、Sakthivel, Kandasamy、Thayumanavan, Rajeswari、Tanaka, Fujie、Barbas III, Carlos F.
DOI:——
日期:——
Vorlaender; Kunze, Chemische Berichte, 1926, vol. 59, p. 2081
作者:Vorlaender、Kunze
DOI:——
日期:——
Organocatalyzed highly stereoselective Michael addition of ketones to alkylidene malonates and nitroolefins using chiral primary-secondary diamine catalysts based on bispidine
based on bispidine have been developed to catalyze the asymmetric Michaeladdition of ketones to alkylidenemalonates and nitroalkenes. The corresponding products were obtained in high yields (up to 99%) with high diastereoselectivities (up to 99:1) and high enantioselectivities (up to 97% ee) under mild conditions using either environmentally benign water as the solvent or no solvent.