97802-97-6Relevant academic research and scientific papers
Catalytic Asymmetric Acyloin Rearrangements of α-Ketols, α-Hydroxy Aldehydes, and α-Iminols by N, N′-Dioxide-Metal Complexes
Dai, Li,Li, Xiangqiang,Zeng, Zi,Dong, Shunxi,Zhou, Yuqiao,Liu, Xiaohua,Feng, Xiaoming
supporting information, p. 5041 - 5045 (2020/07/03)
A highly enantioselective acyloin rearrangement of cyclic α-ketols has been developed with a chiral Al(III)-N,N′-dioxide complex as catalyst. This strategy provided an array of optically active 2-acyl-2-hydroxy cyclohexanones in moderate to good yields with high enantioselectivities. The asymmetric isomerizations of acyclic α-hydroxy aldehydes and α-iminols were achieved as well under modified conditions, affording the corresponding chiral α-hydroxy ketones and α-amino ketones in moderate results. Moreover, further transformations of product to enantioenriched diols were carried out.
Cyclopentane Formation from Flexible Precursors Using Samarium(II) Reagents
Aretz, Christopher D.,Escobedo, Humberto,Cowen, Bryan J.
, p. 1880 - 1884 (2018/05/09)
Three efficient methods for five-membered ring carbocycle synthesis have been developed from simple starting materials using samarium(II) reagents. A Reformatsky aldol reaction proceeded efficiently with samarium(II) iodide using lithium bromide as an additive. A new intramolecular alkylation of a samarium enolate was realized with a pendant sulfonate ester leaving group. Pinacol cyclization of a simple diketone was also demonstrated giving a diol product in high stereoselectivity. A promising lead result has been established demonstrating enantioselectivity in a chiral ligand controlled Reformatsky aldol reaction.
Direct catalytic asymmetric three-component Kabachnik-fields reaction
Cheng, Xu,Goddard, Richard,Buth, Gernot,List, Benjamin
supporting information; experimental part, p. 5079 - 5081 (2009/03/11)
(Chemical Equation Presented) As mimics of α-amino acids, α-amino phosphonates have great promise as antibacterial and anti-HIV agents as well as protease inhibitors. Racemic α-branched aldehydes react, in the presence the new chiral phosphoric acid catalyst 1, directly with p-anisidine (PMPNH2) and a phosphite to furnish β-branched α-amino phosphonates highly diastereoselectively and enantioselectively. Anth = anthracenyl.
Scope and mechanism of the intermolecular addition of aromatic aldehydes to olefins catalyzed by Rh(I) olefin complexes
Roy, Amy H.,Lenges, Christian P.,Brookhart, Maurice
, p. 2082 - 2093 (2007/10/03)
Rhodium (I) bis-olefin complexes Cp*Rh(VTMS)2 and Cp?Rh(VTMS)2 (Cp* = C5Me5, Cp? = C5-Me4CF3, VTMS = vinyl trimethylsilane) were found to catalyze the addition of aromatic aldehy
Palladium-catalyzed coupling of thiol esters with aryl and primary and secondary alkyl organoindium reagents
Fausett, Bryan W.,Liebeskind, Lanny S.
, p. 4851 - 4853 (2007/10/03)
Thiol esters and organoindium reagents undergo palladium-catalyzed cross-coupling under mild conditions to give ketones in moderate to excellent yields. Aryl and primary/ secondary alkyl organoindium reagents can be used as coupling partners. This method has two advantages over the cross-coupling of thiol esters with boron and tin reagents: (1) no added copper reagent is required to mediate the reaction and (2) for the case of alkyl transfer, no added base is required to activate organoindium reagents for cross-coupling as is required for the coupling of alkyl boron reagents with thiol esters.
A new efficient and selective synthesis of ketones from alkanes or cycloalkanes, CO, and silanes in the presence of aprotic superacids
Akhrem,Churilova,Orlinkov,Afanas'eva,Vitt,Petrovskii
, p. 918 - 923 (2007/10/03)
A new approach to the direct synthesis of ketones from alkanes or cycloalkanes (RH), CO, and silanes is proposed. Ketones were obtained in 50-97% yields from propane, butane, cyclopentane, cyclohexane, and methylcyclopentane on treatment with CO and silanes (Me4Si, Et4Si, or m-and p-XC6H4SiMe3, where X = Cl, Me, OMe) in the presence of CX4 · 2AlBr3 (X = Br, Cl) superacids at 0 °C. The reactions with m-and p-XC6H4SiMe3 (X = Cl, Me) occur regioselectively to give m-ketones from m-silanes and p-ketones from p-silanes. However, the only product, p-MeOC6H4COR, is formed both from m-and p-MeOC6H4SiMe3. The reaction of Cyclo-C5H9CO+ with BzSiMe3 results in an organosilicon ketone, Me3SiCH2QH4COC5H9, while in the presence of an excess of an acylating system (after alcoholysis), Me2Si(OR′)CH2C6H4COR is formed.
Ring Contraction of 2-Chlorocyclohexanone with Grignard Reagents
Hori, Mikio,Kataoka, Tadashi,Shimizu, Hiroshi,Imai, Eiji,Iwamura, Tatsunori,Maeda, Kaori
, p. 3599 - 3605 (2007/10/02)
The reaction of 2-chlorocyclohexanone with phenylmagnesium bromide in refluxing tetrahydrofuran unexpectedly afforded the ring-contracted product, cyclopentyl phenyl ketone, as the main product in moderate yield.The reactivities of several cyclic 2-haloketones were examined.Keywords - 2-chlorocyclohexanone; Grignard reaction; ring contraction; cyclopentyl phenyl ketone; solvent effect; THF; conformational isomer
