- tert-Butoxy-Radical-Promoted α-Arylation of Alkylamines with Aryl Halides
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In the presence of a tert-butoxy radical precursor, the reaction of alkylamines with aryl halides was found to give α-arylated alkylamines through homolytic aromatic substitution of the halogen atoms.
- Ueno, Ryota,Ikeda, Yuko,Shirakawa, Eiji
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supporting information
p. 4188 - 4193
(2017/08/07)
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- Catalytic racemisation of chiral amines and application in dynamic kinetic resolution
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A mild and efficient procedure for the racemisation of optically active amines has been developed and applied to the dynamic kinetic resolution (DKR) of a racemic amine. Pentamethylcyclopentadienyliridium (III) iodide dimer dissolved in a convenient solvent is the precatalyst that reacts in situ with primary, secondary, or tertiary amines to form what we have named a SCRAM catalyst. This is able to dehydrogenate a substrate amine to form an imine, which, depending upon the reaction conditions, is then reduced back to the amine. When an optically active amine is mixed with the iridium precatalyst, racemisation is observed. The SCRAM catalyst is used under mild conditions compatible with suitable enzymes and acyl donors, and thus the DKR of an amine has been effected, giving significantly higher yield than if the enzyme alone was used. A mixed carbonate was identified as the optimal acyl donor, giving a carbamate product that is readily removed by acidic hydrolysis.
- Blacker, A. John,Stirling, Matthew J.,Page, Michael I.
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p. 642 - 648
(2012/12/31)
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- (2S)-1-(arylacetyl)-2-(aminomethyl)piperidine derivatives: Novel, highly selective κ opioid analgesics
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This paper describes the synthesis and structure-activity relationships as κ opioid analgesics of a novel class of 1-(arylacetyl)-2-(aminomethyl)piperidine derivatives (8). The active conformation of the pharmacophore, with a torsional angle (N1C2C7N8) of 60°, was defined with computational studies and 1H NMR. A quantitative structure-activity relationship study of the arylacetic moiety substitution indicated that the presence of an electron-withdrawing and lipophilic substituent in para and/or meta positions is required for good analgesic activity and κ affinity. The lead compounds (2S)-1-[(3,4-dichlorophenyl)acetyl]-2-(pyrrolidin-1-ylmethyl) piperidine hydrochloride (14) and (2S)-1-[[4-(trifluoromethyl)phenyl]acetyl]-2-(pyrrolidin-1- ylmethyl)piperidine hydrochloride (21) are the most κ/μ selective (respectively 6500:1 and 4100:1) and among the most potent (K(i) κ 0.24 and 0.57 nM, respectively) κ ligands identified so far. In the mouse tail flick model of antinociception, compound 14 (ED50 = 0.05 mg/kg sc) was 25 times more potent than morphine and 16 times more potent than the standard κ ligand U-50488.
- Vecchietti,Giordani,Giardina,Colle,Clarke
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p. 397 - 403
(2007/10/02)
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- ON THE GIF OXIDATION OF ALICYCLIC TERTIARY AMINES
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Oxidation of various tertiary amines by the GifIV system based on iron catalyst associated with a reductant (zinc) and molecular oxigen, led to a mixture of the keto-derivatives and the corresponding lactams.Steric hindrance and electron withdrawing substituents exert a deactivating effect on the oxidation.
- Barton, D.H.R,Boivin, J.,Gaudin D.,Jankowski, K.
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p. 1381 - 1382
(2007/10/02)
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- BASE-CATALYSED RACEMIZATION OF NICOTINE
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Catalytic activities of various bases on the racemisation of nicotine were investigated.S-(-)-Nicotine was completely racemised by refluxing with a catalytic amount of potassium-t-butoxide for a short time.Thus, a facile preparation method of racemic nicotine was provided.
- Tsujino, Yasuko,Shibata, Saizo,Katsuyama, Akio,Kisaki, Takuro,Kaneko, Hajime
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p. 2151 - 2154
(2007/10/02)
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