Palladium-Catalyzed Oxidative Synthesis of α-Acetoxylated Enones from Alkynes
作者:Tuo Jiang、Xu Quan、Can Zhu、Pher G. Andersson、Jan-E. Bäckvall
DOI:10.1002/anie.201600696
日期:2016.5.4
report a palladium-catalyzed oxidative functionalization of alkynes to generate α-acetoxylated enones in one step. A range of functional groups are well-tolerated in this reaction. Mechanistic studies, including the use of (18) O-labeled DMSO, revealed that the ketone oxygen atom in the product originates from DMSO.
我们报告了一种钯催化的炔烃氧化官能化,一步生成α-乙酰氧基化烯酮。一系列官能团在此反应中具有良好的耐受性。包括使用 (18) O 标记的 DMSO 在内的机理研究表明,产品中的酮氧原子源自 DMSO。
Direct Umpolung Morita–Baylis–Hillman like α‐Functionalization of Enones via Enolonium Species
作者:Shlomy Arava、Sourav K. Santra、Gulab K. Pathe、Raja Kapanaiah、Alex M. Szpilman
DOI:10.1002/anie.202005286
日期:2020.8.24
Morita–Baylis–Hillman type intermediates and application to the α‐functionalization of enone C−H bonds. This reaction gives direct access to α‐chloro‐enones, 1,2‐diketones and α‐tosyloxy‐enones. The latter are important intermediates for cross‐coupling reaction and, to the best of our knowledge, cannot be made in a single step from enones in any other way. The proposed mechanism is supported by spectroscopic
ketones using Koser’s hypervalent iodine reagent is reported. A variety of acyloxy groups from long-chain aliphatic, aromatic, α,β-unsaturated carboxylic acids have been installed efficiently for the first time. The oxyacylated adducts were used for the preparation of densely functionalized chiral δ-lactones and cyclopentenes using carbene organocatalysis.
A Simple Synthetic Route to Enantiopure α-Hydroxy Ketone Derivatives by Asymmetric Hydrogenation
作者:Tian Sun、Xumu Zhang
DOI:10.1002/adsc.201200224
日期:2012.11.26
DuanPhos has been proved to be the most effective ligand for this reaction. The high yield and enantioselectivity of the asymmetric hydrogenation of the α-ketone enol acetates represents a feasible syntheticroute to important pharmaceutical building blocks: α-hydroxy ketones.
An Unprecedented (Semi)Favorskii Rearrangement. Evidence for the 2-(Acyloxy)cyclopropanones
作者:Santu Sadhukhan、Beeraiah Baire
DOI:10.1021/acs.orglett.8b00218
日期:2018.4.6
Discovery and development of an unprecedented (semi)Favorskiirearrangement has been reported. The intermediacy of structurally singular (acyloxy)cyclopropanones has been unraveled by fruitful control experiments including a crossover experiment. This class of cyclopropanones is found to be inert for classical Favorskii functionalization and preferably undergoes a decycloisomerization (ring–chain valence