71823-42-2Relevant academic research and scientific papers
Highly enantioselective iridium-catalyzed hydrogenation of α,β-unsaturated esters
Li, Jia-Qi,Quan, Xu,Andersson, Pher G.
supporting information, 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
On the cis-Effect of Radical Addition Reactions at Alkenes
Giese, Bernd,Lachhein, Stephen
, p. 1616 - 1620 (2007/10/02)
The trans-alkenes 2e - h react faster with cyclohexyl radicals than the cis-alkenes 3e - h (Table 1).Radical addition reactions at alkylidenemalonic esters 1 show that this cis-effect increases with the bulkyness of the substituents (Table 1).However, the difference in the reactivity between trans- and cis-alkenes exerts no effect on the regioselectivity (Table 3).It is concluded that the reason for the cis-effect is a twisting of the ?-system that influences the reactivity of both vinylic C-atoms to the same extent.
