2498-24-0Relevant articles and documents
Can Heteroarenes/Arenes Be Hydrogenated Over Catalytic Pd/C Under Ambient Conditions?
Tanaka, Nao,Usuki, Toyonobu
, p. 5514 - 5522 (2020/07/24)
Hydrogenation of over a dozen aromatic compounds, including both heteroarenes and arenes, over palladium on carbon (Pd/C, 1–100 molpercent) with H2-balloon pressure at room temperature is reported. Analyses using pyridine as a model substrate revealed that acetic acid was the best solvent, as using only 1 molpercent Pd/C provided piperidine quantitatively. Substrate scope analysis and density functional theory calculations indicated that reaction rates are highly dependent on frontier molecular orbital characteristics and the steric bulkiness of substituents. Moreover, the established method was used for the concise synthesis of the anti-Alzheimer drug donepezil (Aricept?).
EFFECT OF THE STRUCTURE OF THE SUBSTRATE AND NUCLEOPHILE ON THE REACTION RATES OF ARYLSULFONYLVINYLTRIALKYLAMMONIUM SALTS WITH AMINES
Popov, A. F.,Kravchenko, V. V.,Kostenko, L. I.,Kotenko, A. A.,Kovach, N. A.
, p. 1915 - 1917 (2007/10/02)
The kinetics of the reactions of arylsulfonylvinyltrialkylammonium salts with primary and secondary aliphatic amines in acetonitrile at 25 deg C were studied.On the basis of the low sensitivity of the reaction of β-(p-nitrophenylsulfonyl)vinyltriethylammonium chloride with alkylamines to the effect of the electronic and steric factors in the structure of the amines it was concluded that the transition state of the process is "looser" than in the reactions of the analogous substrates with a halogen as leaving group.The effect of the structure of the leaving trialkylammonium group on the rate of its substitution by the amino group was studied for the reaction of β-(p-nitrophenylsulfonyl)vinyltrialkylammonium chlorides with piperidine.The obtained data indicate that the process take place by an addition-elimination mechanism.
