28830-48-0Relevant academic research and scientific papers
Copper-catalyzed α-methylenation of benzylpyridines using dimethylacetamide as one-carbon source
Itoh, Masaki,Hirano, Koji,Satoh, Tetsuya,Miura, Masahiro
supporting information, p. 2050 - 2053 (2014/05/06)
The direct α-methylenation of benzylpyridines was achieved using N,N-dimethylacetamide (DMA) as a one-carbon source under copper catalysis. An intermediary species was detected at an early stage, and a possible mechanism was proposed. Additionally, α-oxygenation and dimerization of benzylpyridines could also be performed efficiently.
Control of the Stereochemistry of Kinetic Protonation: Intramolecular Proton Delivery
Zimmerman, Howard E.,Ignatchenko, Alexey
, p. 6635 - 6645 (2007/10/03)
Four decades ago, we noted that for delocalized carbanions and enols the protonation transition state is close to sp2 hybridized and that, as a consequence, under kinetic control protonation takes place from the less hindered approach, most often with formation of the less stable of two possible stereoisomers. The initial report was followed by an extensive series of examples. Nevertheless, a major question remained, namely whether it was possible to deliver the proton to the more hindered face of such a species using intramolecular proton transfer. To this end, silyl ether precursors to the enols of 3-benzoyl-endo-6-phenyl-exo-6-pyridylbicyclo[3.1.0]hexane and its endo-6-pyridyl-exo-6-phenyl stereoisomer were synthesized. The corresponding enols were generated with fluoride anion. The endo-phenyl enol stereoisomers, on kinetic protonation, led stereoselectively to the endo-3-benzoyl product resulting from the less hindered protonation. In stark contrast, the endo-6-pyridyl enol isomer led stereoselectively to the exo-3-benzoyl ketone by intramolecular proton delivery. However, the kinetic orders of the stereochemistries differ; the intramolecular process requires additional proton donor molecules. The log of the ratio of the two stereochemistries is linear with the log of the proton donor concentration with the slope giving the difference in kinetic orders. An aromatic cyclic 14 electron Hueckel transition state is proposed. Additionally, the roles of acyl, nitro and cyano delocalizing groups were analyzed with ab initio computations.
Substituent Effect on the Electrochemical Oxidation of Arylmethyl Anions. 4. Effect of Pyridine Rings
Bank, Shelton,Gernon, Michael
, p. 5105 - 5111 (2007/10/02)
Electrochemical oxidation of the lithium anions of isomeric benzylpyridines and pyridyldiphenylmethanes was examined by cyclic and differential pulse voltammetry in tetrahydrofuran solution.The oxidation processes are dependent on the nitrogen position an
Synthesis of Symmetrical Poly(pyridin-2-yl)ethane Ligands
Canty, Allan J.,Minchin, Nigel J.
, p. 1063 - 1069 (2007/10/02)
Reaction of lithium derivatives of pyridin-2-ylmethanes, (C5H4N)CRR'-Li+, with mercury (II) iodide results in precipitation of mercury, and formation of symmetrical poly(pyridin-2-yl)ethanes 2 (R = H, R' = Ph; R = Me, R' = Ph; R =
Mechanism of Direct Side-chain Acylamination and Aminoarylation of 2- and 4-Picoline 1-Oxides
Abramovitch, Rudolph A.,Abramovitch, Dorota A.,Tomasik, Piotr
, p. 561 - 562 (2007/10/02)
The isolation of radical coupling products and the observation of appropriate C.I.N.D.P. signals suggest that most of the title reactions proceed by homolysis of the anhydro-bases (4) or (9) followed by radical recombinations; a diazo-oxy-Cope rearrangement may still account for the formation of α-acylamination products.
