scholarly journals Hydrogenation of unactivated enamines to tertiary amines: rhodium complexes of fluorinated phosphines give marked improvements in catalytic activity

2015 ◽  
Vol 11 ◽  
pp. 622-627 ◽  
Author(s):  
Sergey Tin ◽  
Tamara Fanjul ◽  
Matthew L Clarke
Keyword(s):  
Catalytic Activity ◽  
Environmentally Benign ◽  
Acid Extraction ◽  
Rhodium Complexes ◽  
Tertiary Amines

In the hydrogenation of sluggish unactivated enamine substrates, Rh complexes of electron-deficient phosphines are demonstrated to be far more reactive catalysts than those derived from triphenylphosphine. These operate at low catalyst loadings (down to 0.01 mol %) and are able to reduce tetrasubstituted enamines. The use of the sustainable and environmentally benign solvent (R)-limonene for the reaction is also reported with the amine isolated by acid extraction.

Phosphines with 2-imidazolium ligands enhance the catalytic activity and selectivity of rhodium complexes for hydrosilylation reactions

2010 ◽  
Vol 695 (3) ◽  
pp. 431-436 ◽  
Author(s):  
Jiayun Li ◽  
Jiajian Peng ◽  
Ying Bai ◽  
Guodong Zhang ◽  
Guoqiao Lai ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Rhodium Complexes

A facile approach to fabricate halloysite/metal nanocomposites with preformed and in situ synthesized metal nanoparticles: a comparative study of their enhanced catalytic activity

2015 ◽  
Vol 44 (19) ◽  
pp. 8906-8916 ◽  
Author(s):  
Sankar Das ◽  
Subhra Jana
Keyword(s):  
Catalytic Activity ◽  
Comparative Study ◽  
Metal Nanoparticles ◽  
Heterogeneous Catalysts ◽  
Cost Effective ◽  
Environmentally Benign ◽  
Metal Nanocomposites

Halloysite/metal nanocomposites have been synthesized through the immobilization of preformed and in situ synthesized metal nanoparticles over halloysite surfaces, which in turn produce efficient, cost-effective, and environmentally benign heterogeneous catalysts.

Catalytic activity of homogeneous and silica-anchored rhodium complexes

1993 ◽  
Vol 50 (1-2) ◽  
pp. 71-74 ◽  
Author(s):  
M. Čapka ◽  
M. Czakoová ◽  
J. Hjortkjaer ◽  
U. Schubert
Keyword(s):  
Catalytic Activity ◽  
Rhodium Complexes

scholarly journals Cu(II) and magnetite nanoparticles decorated melamine-functionalized chitosan: A synergistic multifunctional catalyst for sustainable cascade oxidation of benzyl alcohols/Knoevenagel condensation

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Zahra Alirezvani ◽  
Mohammad G. Dekamin ◽  
Ehsan Valiey
Keyword(s):  
Catalytic Activity ◽  
Knoevenagel Condensation ◽  
Ambient Pressure ◽  
Reaction Medium ◽  
Environmentally Benign ◽  
One Pot ◽  
Benzyl Alcohols ◽  
External Magnet ◽  
Multistep Synthesis ◽  
Multifunctional Catalyst

AbstractThe uniform decoration of Cu(II) species and magnetic nanoparticles on the melamine-functionalized chitosan afforded a new supramolecular biopolymeric nanocomposite (Cs-Pr-Me-Cu(II)-Fe3O4). The morphology, structure, and catalytic activity of the Cs-Pr-Me-Cu(II)-Fe3O4 nanocomposite have been systematically investigated. It was found that Cs-Pr-Me-Cu(II)-Fe3O4 nanocomposite can smoothly promote environmentally benign oxidation of different benzyl alcohol derivatives by tert-butyl hydroperoxide (TBHP) to their corresponding benzaldehydes and subsequent Knoevenagel condensation with malononitrile, as a multifunctional catalyst. Interestingly, Fe3O4 nanoparticles enhance the catalytic activity of Cu(II) species. The corresponding benzylidenemalononitriles were formed in high to excellent yields at ambient pressure and temperature. The heterogeneous Cs-Pr-Me-Cu(II)-Fe3O4 catalyst was also very stable with almost no leaching of the Cu(II) species into the reaction medium and could be easily recovered by an external magnet. The recycled Cs-Pr-Me-Cu(II)-Fe3O4 was reused at least four times with slight loss of its activity. This is a successful example of the combination of chemo- and bio-drived materials catalysis for mimicing biocatalysis as well as sustainable and one pot multistep synthesis.

Sign in / Sign up

Export Citation Format

Share Document