1443215-58-4Relevant academic research and scientific papers
A General Method for α-Oxyacylation of Vinyl Ketones Using Koser's Reagent
Azaz, Tazeen,Mishra, Bal Krishna,Mourya, Hemlata,Pandey, Chandra Bhan,Ram, Bali,Tiwari, Bhoopendra
, p. 17318 - 17327 (2021/12/02)
A direct general method for the preparation of α-oxyacylated vinyl 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.
Direct Umpolung Morita–Baylis–Hillman like α-Functionalization of Enones via Enolonium Species
Arava, Shlomy,Kapanaiah, Raja,Pathe, Gulab K.,Santra, Sourav K.,Szpilman, Alex M.
supporting information, p. 15171 - 15175 (2020/07/04)
Herein we report on the umpolung of 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 studies. The key initial step involves conjugate attack of an amine (DABCO or pyridine), likely assisted by hypervalent iodine acting as a Lewis acid leading to formation of an electrophilic β-ammonium-enolonium species. Nucleophilic attack by acetate, tosylate, or chloride anion is followed by base induced elimination of the ammonium species to give the noted products. Hydrolysis of α-acetoxy-enones lead to formation of 1,2-diketones. The α-tosyl-enones participate in Negishi coupling reactions under standard conditions.
An Unprecedented (Semi)Favorskii rearrangement. evidence for the 2-(Acyloxy)cyclopropanones
Sadhukhan, Santu,Baire, Beeraiah
supporting information, p. 1748 - 1751 (2018/04/14)
Discovery and development of an unprecedented (semi)Favorskii rearrangement 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 tautomerism) to α-(acyloxy)enones. A cascade conversion of α,α-diiodo-α′-acetoxyketones to (acyloxy)cyclopropanones via α-iodo-α′-acetoxyketones has been achieved by the synchronous dual basicity (Lewis and Br?nsted) of amines. The overall process is found to be very general for diverse substrates and highly efficient.
Palladium-Catalyzed Oxidative Synthesis of α-Acetoxylated Enones from Alkynes
Jiang, Tuo,Quan, Xu,Zhu, Can,Andersson, Pher G.,B?ckvall, Jan-E.
supporting information, p. 5824 - 5828 (2016/05/09)
We 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 18O-labeled DMSO,
A simple synthetic route to enantiopure α-hydroxy ketone derivatives by asymmetric hydrogenation
Sun, Tian,Zhang, Xumu
supporting information, p. 3211 - 3215 (2013/01/15)
High enantioselectivities (up to 99% ee) have been observed for the catalytic asymmetric hydrogenation of the α-ketone enol acetates. 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 synthetic route to important pharmaceutical building blocks: α-hydroxy ketones. Copyright
