21866-70-6Relevant articles and documents
Saegusa Oxidation of Enol Ethers at Extremely Low Pd-Catalyst Loadings under Ligand-free and Aqueous Conditions: Insight into the Pd(II)/Cu(II)-Catalyst System
Zhu, Quan,Luo, Yunsong,Guo, Yongyan,Zhang, Yushun,Tao, Yunhai
, p. 5463 - 5476 (2021/05/05)
A highly efficient and practical Pd(II)/Cu(OAc)2-catalyst system of Saegusa oxidation, which converts enol ethers to the corresponding enals with a number of diverse substrates at extremely low catalyst loadings (500 mol ppm) under ligand-free and aqueous conditions, is described. Its synthetic utility was demonstrated by large-scale applications of the catalyst system to important nature molecules. This work allows Saegusa oxidation to become a highly practical approach to preparing enals and also suggests new insight into the Pd(II)/Cu(II)-catalyst system for dehydrogenation of carbonyl compounds and decreasing Pd-catalyst loadings.
Stereodefined rhodium-catalysed 1,4-H/D delivery for modular syntheses and deuterium integration
Cheng, Bao,Fang, Huayi,Ma, Shengming,Qian, Hui,Wang, Weiyi,Yu, Yibo,Zhang, Xue
, p. 586 - 594 (2021/07/17)
Deuterium-incorporated compounds are of high interest owing to their importance in the pharmaceutical industry, organic synthesis and materials science. So far, the integration of deuterium into the inert, saturated magic methyl or methylene groups of covalent molecules remains challenging. Here, we present a 1,4-H delivery of allylic metallic species to provide a highly stereoselective and straightforward approach to 3-methyl-2(E)-enals or -enones from readily available 2,3-allenols and organoboronic acids. The reaction accommodates many synthetically versatile functional groups as well as multi-pharmacophores, and is not limited to the formation of 3-methyl derivatives. By applying 1,4-H or D delivery, deuterium atom(s) from differently deuterated allenols can be edited into the methyl or methylene groups of versatile organic skeletons, resulting in the efficient formation of 4-monodeuterated, 1,4- and 4,4-doubly deuterated, and 4,4,4-triply deuterated 2(E)-enals or -enones. These powerful platform molecules can provide straightforward paths to other deuterated compounds for different purposes. [Figure not available: see fulltext.].
Deep eutectic solvent-catalyzed Meyer-Schuster rearrangement of propargylic alcohols under mild and bench reaction conditions
Ríos-Lombardía, Nicolás,Cicco, Luciana,Yamamoto, Kota,Hernández-Fernández, José A.,Morís, Francisco,Capriati, Vito,García-álvarez, Joaquín,González-Sabín, Javier
supporting information, p. 15165 - 15168 (2020/12/21)
The Meyer-Schuster rearrangement of propargylic alcohols into α,β-unsaturated carbonyl compounds has been revisited by setting up an atom-economic process catalyzed by a deep eutectic solvent FeCl3·6H2O/glycerol. Isomerizations take place smoothly, at room temperature, under air and with short reaction times. The unique solubilizing properties of the eutectic mixture enabled the use of a substrate concentration up to 1.0 M with the medium being recycled up to ten runs without any loss of catalytic activity. This journal is