30668-14-5Relevant academic research and scientific papers
Catalytic α-Hydroarylation of Acrylates and Acrylamides via an Interrupted Hydrodehalogenation Reaction
Cherney, Emily C.,Engle, Keary M.,Gurak, John A.,Joe, Candice L.,Vasquez, Alena M.
supporting information, p. 10477 - 10484 (2020/08/07)
The palladium-catalyzed, α-selective hydroarylation of acrylates and acrylamides is reported. Under optimized conditions, this method is highly tolerant of a wide range of substrates including those with base sensitive functional groups and/or multiple enolizable carbonyl groups. A detailed mechanistic study was undertaken, and the high selectivity of this transformation was shown to be enabled by the formation of a [PdII(Ar)(H)] intermediate, which performs selective hydride insertion into the β-position of α,β-unsaturated carbonyl compounds.
Rh(DPEPhos)-Catalyzed Alkyne Hydroacylation Using β-Carbonyl-Substituted Aldehydes: Mechanistic Insight Leads to Low Catalyst Loadings that Enables Selective Catalysis on Gram-Scale
Barwick-Silk, James,Hardy, Simon,Willis, Michael C.,Weller, Andrew S.
supporting information, p. 7347 - 7357 (2018/06/04)
The detailed mechanism of the hydroacylation of β-amido-aldehyde, 2,2-dimethyl-3-morpholino-3-oxopropanal, with 1-octyne using [Rh(cis-κ2-P,P-DPEPhos)(acetone)2][BArF4]-based catalysts, is described [ArF = (CF3)2C6H3]. A rich mechanistic landscape of competing and interconnected hydroacylation and cyclotrimerization processes is revealed. An acyl-hydride complex, arising from oxidative addition of aldehyde, is the persistent resting state during hydroacylation, and quaternary substitution at the β-amido-aldehyde strongly disfavors decarbonylation. Initial rate, KIE, and labeling studies suggest that the migratory insertion is turnover-limiting as well as selectivity determining for linear/branched products. When the concentration of free aldehyde approaches zero at the later stages of catalysis alkyne cyclotrimerization becomes competitive, to form trisubstituted hexylarenes. At this point, the remaining acyl-hydride turns over in hydroacylation and the free alkyne is now effectively in excess, and the resting state moves to a metallacyclopentadiene and eventually to a dormant α-pyran-bound catalyst complex. Cyclotrimerization thus only becomes competitive when there is no aldehyde present in solution, and as aldehyde binds so strongly to form acyl-hydride when this happens will directly correlate to catalyst loading: with low loadings allowing for free aldehyde to be present for longer, and thus higher selectivites to be obtained. Reducing the catalyst loading from 20 mol % to 0.5 mol % thus leads to a selectivity increase from 96% to ～100%. An optimized hydroacylation reaction is described that delivers gram scale of product, at essentially quantitative levels, using no excess of either reagent, at very low catalyst loadings, using minimal solvent, with virtually no workup.
Selective catalytic sp3 C-O bond cleavage with C-N bond formation in 3-alkoxy-1-propanols
Chen, Cheng,Hong, Soon Hyeok
supporting information; experimental part, p. 2992 - 2995 (2012/07/28)
The ruthenium catalyzed selective sp3 C-O cleavage with amide formation was reported in reactions of 3-alkoxy-1-propanol derivatives and amines. The cleavage only occurs at the C3-O position even with 3-benzyloxy-1-propanol. Based on the experimental results, O-bound and C-bound Ru enolate complexes were proposed as key intermediates for the unique selective sp3 C-O bond cleavage in 3-alkoxy-1-propanols.
N-(lower alkyl)-2-(3'ureidobenzyl)pyrrolidines
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, (2008/06/13)
N-(lower alkyl)-2-(3'-ureidobenzyl)pyrrolidines and N-(lower alkyl)-2-(3'-ureidobenzyl)-5-(lower alkyl)pyrrolidines are useful for lowering intraocular pressure in mammals, for example, in the treatment of glaucoma.
