Supported Cobalt Nanoparticles for Hydroformylation Reactions
作者:Maximilian Franz Hertrich、Florian Korbinian Scharnagl、Anahit Pews‐Davtyan、Carsten Robert Kreyenschulte、Henrik Lund、Stephan Bartling、Ralf Jackstell、Matthias Beller
DOI:10.1002/chem.201806282
日期:2019.4.11
Hydroformylation of olefins has been studied in the presence of specific heterogeneous cobalt nanoparticles. The catalytic materials were prepared by pyrolysis of preformed cobalt complexes deposited onto different inorganic supports. Atomic absorption spectroscopy (AAS) measurements indicated a correlation of catalystactivity and cobalt leaching as well as a strong influence of the heterogeneous
Fluorous soluble polymer catalysts for the fluorous biphase hydroformylation of olefins
作者:Weiping Chen、Lijin Xu、Jianliang Xiao
DOI:10.1039/b000574f
日期:——
Fluorous soluble polymer ligands have been prepared and shown to be active and selective catalysts when combined with rhodium for the fluorous biphase hydroformylation of various olefins.
Iron-catalyzed cross-coupling of Grignard reagents (RMgX) with (E)- and (Z)-enol tosylates proceeded smoothly to give a variety of the corresponding (E)- and (Z)-trisubstituted α,β-unsaturated methyl esters (total 30 examples; 55-98% yield). The simple, mild, stereoretentive method utilized iron(III) chloride (FeCl3), iron(III) acetylacetonate [Fe(acac)3], and iron(III) tris(dibenzylmethane) [Fe(dbm)3]. The (E)- and (Z)-enol tosylates were readily prepared by the reported stereocomplementary tosylation method from methyl β-keto esters or α-formyl esters. Methyl α-formyl esters were obtained via a practical and robust TiCl4-Et3N-mediated α-formylation of methyl esters with methyl formate.
for α,β-disubstituted α,β-unsaturated esters is performed via three general and robust reaction sequences: (i) Ti−Claisen condensation (formylation) of esters to give α-formyl esters (12 examples, 60−99%), (ii) (E)- and (Z)-stereocomplementary enol p-toluenesulfonylation (tosylation) using TsCl−N-methylimidazole (NMI)−Et3N and LiOH (24 examples, 82−99%), and (iii) stereoretentive Suzuki−Miyaura cross-coupling
Rapid hydroformylation of alkyl acrylates in supercritical CO2
作者:Yulai Hu、Weiping Chen、Anna M. Banet Osuna、Jianliang Xiao、Alison M. Stuart、Eric G. Hope
DOI:10.1039/b101043n
日期:——
Fast and regioselective hydroformylation of alkyl acrylates
can readily be accomplished in supercritical CO2
(scCO2), which promotes the reaction probably via
specific solvent–solute interactions.