A versatile organocatalyst for the asymmetric conjugate addition of nitroalkanes to enones
作者:Claire E. T. Mitchell、Stacey E. Brenner、Steven V. Ley
DOI:10.1039/b511441a
日期:——
5-Pyrrolidin-2-yltetrazole performs as an improved catalyst for the asymmetricaddition of a range of nitroalkanes to cyclic and acyclic enones, with good to excellent enantioselectivity.
An efficient, asymmetric organocatalyst-mediated conjugate addition of nitroalkanes to unsaturated cyclic and acyclic ketones
作者:Claire E. T. Mitchell、Stacey E. Brenner、Jorge García-Fortanet、Steven V. Ley
DOI:10.1039/b601877g
日期:——
5-Pyrrolidin-2-yltetrazole is a versatile organocatalyst for the asymmetric conjugateaddition of nitroalkanes to enones. Using this catalyst, this transformation requires short reaction times, tolerates a broad substrate scope, and possibly proceeds via generation of an iminium species.
Asymmetric multifunctional organocatalytic Michael addition of nitroalkanes to α,β-unsaturated ketones
作者:Pengfei Li、Yongcan Wang、Xinmiao Liang、Jinxing Ye
DOI:10.1039/b804540b
日期:——
Cinchona alkaloid derived primary amine thioureas organocatalyzed Michael addition of nitroalkanes to enones in good yield and up to 98% ee and offered a new way to construct quaternary stereocenters from enones and nitroalkanes.
Camphor-derived C1-symmetric chiral diamine organocatalysts for asymmetric Michael addition of nitroalkanes to enones
作者:Yirong Zhou、Qiang Liu、Yuefa Gong
DOI:10.1039/c2ob25922b
日期:——
A series of stable C1-symmetric chiral diamines (2a–2l) were conveniently synthesized by condensing exo-(−)-bornylamine or (+)-(1S,2S,5R)-menthylamine with various commercially available Cbz-protected amino acids. Among them, 2a can efficiently promote the Michael addition of nitroalkanes to a broad scope of enones with high yields (up to 96%) and excellent enantioselectivities (up to 98%) under mild conditions.
Highly enantioselective conjugate addition of nitroalkanes to enones catalyzed by cinchona alkaloid derived primary amine
作者:Wenjing Liu、Desheng Mei、Wei Wang、Wenhu Duan
DOI:10.1016/j.tetlet.2013.05.019
日期:2013.7
A cinchona alkaloid derived primary amine catalyzed conjugate addition of nitroalkanes to enones is described. The process affords the Michael adducts in good yield and with up to 99% ee for both acyclic and cyclic enones.