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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Minimizing Aryloxy Elimination in Rh(I) -Catalyzed Asymmetric Hydrogenation of β-Aryloxyacrylic Acids using a
Yang Li1, Zheng Wang1, Kuiling Ding2,3
1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032 (P. R. China), Fax: (+21) 6416-6128.
Abstract:
The first example of efficient asymmetric hydrogenation of challenging β-aryloxyacrylic acids was realized using a Rh(I) -complex based on the heterocombination of a readily available chiral monodentate secondary phosphine oxide (SPO) and an achiral monodentate phosphine ligand as the catalyst. Excellent enantioselectivities (92->99 % ee) were achieved for a wide variety of chiral β-aryloxypropionic acids with minor aryloxy elimination in most cases. The resultant products were readily transformed into biologically active compounds through simple synthetic manipulations.
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