72277-22-6Relevant articles and documents
Carbonyls as Latent Alkyl Carbanions for Conjugate Additions
Dai, Xi-Jie,Wang, Haining,Li, Chao-Jun
supporting information, p. 6302 - 6306 (2017/05/19)
Conjugate addition of carbon nucleophiles to electron-deficient olefins is one of the most powerful methods for forming carbon–carbon bonds. Despite great achievements in controlling the selectivity, variation of the carbon nucleophiles remains largely underexplored, with this approach relying mostly on organometallic reagents. Herein, we report that naturally abundant carbonyls can act as latent carbon nucleophiles for conjugate additions through a ruthenium-catalyzed process, with water and nitrogen as innocuous byproducts. The key to our success is homogeneous ruthenium(II) catalysis, combined with phosphines as spectator ligands and hydrazine as the reducing agent. This chemistry allows the incorporation of highly functionalized alkyl fragments into a vast array of electron-deficient olefins under mild reaction conditions in a reaction complementary to the classical organometallic-reagent-based conjugate additions mediated or catalyzed by “soft” transition metals.
Highly enantioselective iridium-catalyzed hydrogenation of α,β-unsaturated esters
Li, Jia-Qi,Quan, Xu,Andersson, Pher G.
, p. 10609 - 10616 (2012/11/07)
α,β-Unsaturated esters have been employed as substrates in iridium-catalyzed asymmetric hydrogenation. Full conversions and good to excellent enantioselectivities (up to 99 % ee) were obtained for a broad range of substrates with both aromatic- and aliphatic substituents on the prochiral carbon. The hydrogenated products are highly useful as building blocks in the synthesis of a variety of natural products and pharmaceuticals. Asymmetric hydrogenation: A variety of α,β-unsaturated esters were hydrogenated with high enantioselectivities (see scheme). The hydrogenated products have been used in synthetic transformations as well as in formal total syntheses. Copyright
Tetramethylethylene diamine/trimethylsilyl chloride mediated addition of benzyl copper reagents to α,β-unsaturated esters
Van Heerden, Pieter S.,Bezuidenhoudt, Barend C. B.,Ferreira, Daneel
, p. 12313 - 12322 (2007/10/03)
Several benzylic copper reagents, benzylcopper, 4-methoxybenzylcopper and 1-phenylethylcopper, facilitate the conjugate addition of the corresponding benzyl ligands to α,β-enoates in the presence of tetramethylethylene diamine and trimethylsilyl chloride in high yields.