613670-59-0Relevant academic research and scientific papers
Room-Temperature Benzylic Alkylation of Benzylic Carbonates: Improvement of Palladium Catalyst and Mechanistic Study
Kuwano, Ryoichi,Yokogi, Masashi,Sakai, Ken,Masaoka, Shigeyuki,Miura, Takashi,Won, Sungyong
, p. 1568 - 1579 (2019/09/04)
The palladium catalyst for the nucleophilic substitution of benzyl carbonates was improved by using 1,1′-bis(diisopropylphosphino)ferrocene (DiPrPF) as the ligand. The [Pd(η3-C3H5)(cod)]BF4-DiPrPF catalyst allows the benzylic substitution with soft carbanions to proceed even at 30 °C, affording the desired products in high yields (up to 99% yield). Thermally unstable pyridylmethyl esters are employable as the electrophilic substrates for the benzylic alkylation with the improved catalyst. Furthermore, we investigated the mechanism of the catalytic benzylic alkylation by means of DiPrPF ligand. The palladium(0) complex bearing DiPrPF activates the benzylic C-O bond to form the (benzyl)palladium(II) intermediate at room temperature. The coordination mode of the benzyl ligand would be equilibrium between the η1- and η3-manner. The nucleophile would preferentially react with the η3-benzyl ligand to give the desired product.
Use of acetate as a leaving group in palladium-catalyzed nucleophilic substitution of benzylic esters
Yokogi, Masashi,Kuwano, Ryoichi
, p. 6109 - 6112 (2008/03/12)
The palladium complex prepared in situ from [Pd(η3-C3H5)(cod)]BF4 and bidentate phosphine DPPF was a good catalyst for the nucleophilic substitution of benzyl acetate. Significant acceleration of the palladium-catalyzed substitution was observed when an alcohol was employed as a reaction solvent. The palladium catalyst was effective for the benzylation of various stabilized carbanions, amines, and benzenesulfinate with benzylic acetates.
Palladium-catalyzed benzylation of active methine compounds without additional base: Remarkable effect of 1,5-cyclooctadiene
Kuwano, Ryoichi,Kondo, Yutaka
, p. 3545 - 3547 (2007/10/03)
(Chemical Equation Presented) The palladium complex prepared from DPPF and Cp(η3-C3H5)Pd is an effective catalyst for the alkylation of active methine compounds with benzylic carbonates under neutral conditions. The additi
Palladium-catalyzed nucleophilic benzylic substitutions of benzylic esters
Kuwano, Ryoichi,Kondo, Yutaka,Matsuyama, Yosuke
, p. 12104 - 12105 (2007/10/03)
A palladium complex generated in situ from [Pd(η3-C3H5)(cod)]BF4 and DPPF is a good catalyst for benzylic alkylation of benzyl methyl carbonate with the carbanion of dimethyl malonates. The catalytic reaction is applicable to a wide range of the benzylations of benzylic esters with malonates. The catalytic activity was heavily affected by the bite angle of the bidentate phosphine ligand on palladium. DPEphos ligand is superior to DPPF in the case of palladium-catalyzed benzylic amination of benzylic esters. Copyright
