α-Functionalization of 2-Vinylpyridines via a Chiral Phosphine Catalyzed Enantioselective Cross Rauhut–Currier Reaction
作者:Cong Qin、Yonghai Liu、Yang Yu、Yiwei Fu、Hao Li、Wei Wang
DOI:10.1021/acs.orglett.8b00008
日期:2018.3.2
Herein, 2-vinylpyridines as a newtype of electron-poor system for the asymmetric cross Rauhut–Currier reaction are reported. 2-Vinylpyridines are chemo- and enantioselectively activated by a newly designed chiral phosphine catalyst. The newreaction provides a powerful synthetic tool for accessing structurally diverse, highly valued chiral pyridine building blocks in good yields and with high enantioselectivities
sulfinamide bisphosphine catalysts (Wei‐Phos) were developed. These could be easily prepared from commercially available starting materials. Wei‐Phos has shown good performance in the very challenging intermolecular cross‐Rauhut–Currier reactions of vinyl ketones and 3‐acyl acrylates or 2‐ene‐1,4‐diones, leading to the R‐C products in high yields with up to 99 % ee under 2.5–5 mol% catalyst loading. The highly
Amorphous, soluble, aromatic polymers with high glass transition
申请人:——
公开号:US05306789A1
公开(公告)日:1994-04-26
Amorphous polymers which are soluble in organic solvents and can thus be cast as films have high glass transition temperatures which make them suitable for numerous high temperature applications; the polymers comprise ortho aromatic polyketones, polyphthalazines and polyisoquinolines, the polyphthalazines and polyisoquinolines being readily formed from the polyketones.
versatile 1,4-diketones are smoothly generated under metal-free and external-reductant-free electrolytic conditions. Moreover, the tolerance of various functional groups and decagram-scale experiments have shown the practicability and potential applications of this methodology. Moreover, a range of heterocyclic compounds were easily prepared through follow-up procedures of 1,4-diketones.
已经报道了在未分割的电池中有效氢化不饱和 C C 键的简单电化学方案。在无金属和无外部还原剂的电解条件下顺利生成一系列多功能的1,4-二酮。此外,各种官能团的耐受性和十克规模的实验表明了该方法的实用性和潜在应用。此外,通过1,4-二酮的后续程序可以轻松制备一系列杂环化合物。