4208-57-5Relevant articles and documents
Rh-Catalyzed Coupling of Aldehydes with Allylboronates Enables Facile Access to Ketones
Zhang, Kezhuo,Huang, Jiaxin,Zhao, Wanxiang
supporting information, (2022/02/21)
We present herein a novel strategy for the preparation of ketones from aldehydes and allylic boronic esters. This reaction involves the allylation of aldehydes with allylic boronic esters and the Rh-catalyzed chain-walking of homoallylic alcohols. The key to this successful development is the protodeboronation of alkenyl borylether intermediate via a tetravalent borate anion species in the presence of KHF2 and MeOH. This approach features mild reaction conditions, broad substrate scope, and excellent functional group tolerance. Mechanistic studies also supported that the tandem allylation and chain-walking process were involved.
C5′-alkyl substitution effects on digitoxigenin α-l-glycoside cancer cytotoxicity
Wang, Hua-Yu Leo,Wu, Bulan,Zhang, Qi,Kang, Sang-Woo,Rojanasakul, Yon,O'Doherty, George A.
scheme or table, p. 259 - 263 (2011/06/16)
A highly regio- and stereoselective asymmetric synthesis of various C5′-alkyl side chains of rhamnosyl- and amicetosyl-digitoxigenin analogues has been established via palladium-catalyzed glycosylation with postglycosylated dihydroxylation or diimide reduction. The C5′-methyl group in both α-l-rhamnose and α-l-amicetose digitoxin analogues displayed a steric directed apoptosis induction and tumor growth inhibition against nonsmall cell human lung cancer cells (NCI-H460). The antitumor activity is significantly reduced when the steric hindrance is increased at the C5′-stereocenter.
Unexpectedly high activity of Zn(OTf)2·6H2O in catalytic Friedel-Crafts acylation reaction
He, Fei,Wu, Huayue,Chen, Jiuxi,Su, Weike
, p. 255 - 264 (2008/03/17)
Zn(OTf)2·6H2O was used to promote Friedel-Crafts acylation of aromatics. The work describes the high activity and efficiency of Zn(OTf)2·6H2O in acylation of aromatics, and the catalyst has surpassed most metal triflates in dispensing when dried at high temperature under vacuum before use. Copyright Taylor & Francis Group, LLC.
A new and highly efficient water-soluble copper complex for the oxidation of secondary 1-heteroaryl alcohols by tert-butyl hydroperoxide
Boudreau, Josée,Doucette, Mike,Ajjou, Abdelaziz Nait
, p. 1695 - 1698 (2007/10/03)
The water-soluble copper complex generated in situ from CuCl2 and 2,2′-biquinoline-4,4′-dicarboxylic acid dipotassium salt (BQC), has been revealed as a highly efficient and selective catalyst for the oxidation of secondary 1-heteroaryl alcohols to the corresponding heteroaromatic ketones with aqueous tert-butyl hydroperoxide, under mild conditions. The catalytic system is compatible with different heterocycles such as pyridines, pyrroles, indoles, thiophens, furans, thiazoles, and imidazoles.
Friedel-Crafts acylation of furan and thiophene using ytterbium(III) trifluoromethanesulfonate in [BPy][BF4] ionic liquid
Su, Weike,Wang, Yan
, p. 398 - 400 (2007/10/03)
Friedel-Crafts reactions of furan and thiophene have been catalyzed by ytterbium(III) trifluoromethanesulfonate in [BPy][BF4] (n-butylpyridinium tetrafluoroborate) ionic liquid to produce intermediates of pharmaceuticals with good yields. The catalyzing system [BPy][BF 4]/Yb(OTf)3 could be reused.
HENRY CONDENSATION UNDER HIGH PRESSURE. 2. EFFECT OF AROMATIC ALDEHYDE TYPE AND PRESSURE ON THE YIELD OF ω-NITROSTYRENES AND SECONDARY PROCESSES
Agafonov, N. E.,Sedishev, I. P.,Dudin, A. V.,Kutin, A. A.,Stashina, G. A.,Zhulin, V. M.
, p. 366 - 372 (2007/10/02)
Condensation of aromatic aldehydes (I)-(XX) with EtNO2 and n-PrNO2 in AcOH in the presence of AcONH4 or i-BuNH2 gives primarily ω-nitrostyrenes (Ia, b) - (XXa, b) and small quantities of nitriles (Ic) - (XXc), oximes (Id) - (XXd), and ketones (Ie, f) - (XXe, f).The yields of (Ia, b) - (XXa, b) at P = 1 atm are higher for acceptor substitutents on the aromatic ring whereas at P = 10 kbar, they are higher for donor substituents.High pressures suppress the formation of (Ic-f) - (XXc-f) and the Z-isomers of (Ia, b) - (XXa, b).The high pressure technique is especially useful in the preparation of donor-substituted (Ia, b) - (XXa, b) which are intermediates in the synthesis of the psychotropic β-phenylethylamines.
Palladium-catalyzed acyldemetallation and carbonylation reactions of organomercurials for the synthesis of unsymmetrical ketones
Bumagin, N. A.,More, P. G.,Beletskaya, I. P.
, p. 379 - 388 (2007/10/02)
The palladium-catalyzed acyldemetallation reactions of organomercurials (R2Hg or AlkHgI) provide a mild, selective and general method for the synthesis of unsymmetrical heterocyclic ketones.High yields of ketones (RCOR') were obtained along with small amounts of homocoupling products (R2).The reaction is accelerated by a nucleophilic catalyst with both organic groups of R2Hg taking part in the reaction.The selectivity of the reaction towards the ketone can be increased by carrying out the reaction with a suitable combination of reactants under vacuum.The palladium-catalyzed carbonylation of organomercurials in the presence of ArI is another route to unsymmetrical ketones.The AlkHgI-ArI system undergoes carbonylation in the presence of palladium complex and excess iodide ion under mild conditions to give high yields of unsymmetrical ketones.The selectivity and rate of the reaction depend upon the nature of the catalyst, solvent and the concentration of iodide ion.
