4746-48-9Relevant articles and documents
Catalytic Transfer Hydration of Cyanohydrins to α-Hydroxyamides
Kanda, Tomoya,Naraoka, Asuka,Naka, Hiroshi
supporting information, p. 825 - 830 (2019/01/14)
We report the palladium(II)-catalyzed transfer hydration of cyanohydrins to α-hydroxyamides by using carboxamides as water donors. This method enables selective hydration of various aldehyde- and ketone-derived cyanohydrins to afford α-mono- and α,α-disubstituted-α-hydroxyamides, respectively, under mild conditions (50 °C, 10 min). The direct conversion of fenofibrate, a drug bearing a benzophenone moiety, into a functionalized α,α-diaryl-α-hydroxyamide was achieved by means of a hydrocyanation-transfer hydration sequence. Preliminary kinetic studies and the synthesis of a site-specifically 18O-labeled α-hydroxyamide demonstrated the carbonyl oxygen transfer from the carboxamide reagent into the α-hydroxyamide product.
Redox-neutral α-cyanation of amines
Ma, Longle,Chen, Weijie,Seidel, Daniel
supporting information, p. 15305 - 15308 (2012/10/29)
α-Aminonitriles inaccessible by traditional Strecker chemistry are obtained in redox-neutral fashion by direct amine α-cyanation/N-alkylation or alternatively, α-aminonitrile isomerization. These unprecedented transformations are catalyzed by simple carboxylic acids.
Influence of Nitrogen Base Ligation and Hydrogen Bonding on the Rate Constants for Oxygen Transfer from Percarboxylic Acids and Alkyl Hydroperoxides to (meso-Tetraphenylporphinato>manganese(III) Chloride
Yuan, Lung-Chi,Bruice, Thomas C.
, p. 1643 - 1650 (2007/10/02)
Equilibrium constants for axial ligation of imidazole (ImH), N-methylimidazole (N-MeIm), 4'-(imidazo-1-yl)-acetophenone (NAcPhIm), 2,6-lutidine (2,6-Py), and 3,4-lutidine (3,4-Py) with (meso-tetraphenylporphinato)manganese chloride ((TPP)MnIIICl) have been determined.The rates of oxygen atom transfer from percarboxylic acids and alkyl hydroperoxides (YOOH) to the manganese(III) porphyrin in the presence of varying concentrations of the nitrogen bases were determined.For this purpose, 2,2-diphenyl-1-picrylhydrazine (DPPH) was employed as a trap for the generated higher valent oxo-manganese porphyrin species.From the equilibrium and kinetic data, there was then calculated the second-order rate constants for oxygen atom transfer from YOOH compounds to the species (TPP)MnIIICl, TPP(Cl)MnIIIN, and TPP(Cl)MnIIIN2 (where N = ImH, N-MeIm, and 3,4-Py).Only the percarboxylic acids exhibit measurable rate constants for oxygen transfer to (TPP)MnIIICl, whereas alkyl hydroperoxides and percarboxylic acids transfer oxygen to the TPP(Cl)MnIIIN species.Of the species TPP(Cl)MnIIIN2, reaction with YOOH compounds is seen only when N is imidazole.This is attributed to an equilibrium of the unreactive bis axially ligated TPP(Cl)MnIII(ImH)2 with the reactive isomeric mono axial-ligated complex Cl(1-)...H-Im...H-Im...MnIIITPP.Nitrogen base ligation of (TPP)MnIIICl provides minimally a 1E3 increase in the rate constants for oxygen transfer in methylene chloride.Linear free-energy plots of the log of the second-order rate constants for oxygen transfer from YOOH vs. the pKa of YOH establish that β1g for oxygen transfer in which heterolytic O-O bond scission is rate-determining is large and negative.The value of β1g when oxygen transfer involves rate-determining homolytic O-O bond scission is small and negative.
