73788-99-5Relevant articles and documents
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
Asymmetric Synthesis of 2-Substituted Butyrolactones and Valerolactones
Meyers, A. I.,Yamamoto, Yukio,Mihelich, Edward D.,Bell, Richard A.
, p. 2792 - 2796 (2007/10/02)
The use of chiral oxazolines 1, 2, 5, and 8 under asymmetrically induced alkylation conditions gave α-substituted oxazolines 3, 6, 9, and 13 which were hydrolyzed to α-substituted butyro- and valerolactones 4 and 11.Either enantiomer of the lactones could be prepared in predictable absolute configuration by reversing the order of alkyl group introduction.The lactones were prepared in 60-86 percent enantiomeric excess which was determined by either chemical correlation or high-pressure liquid chromatography of the diastereomers 10.
