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CTH compilation, questions, future directions

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indole_amine:
Looks like a novel "green chem" approach... ;)

Hydrogen-Rich Gas Production from Biomass Catalytic Gasification
(Lv, P.; Chang, J.; Wang, T.; Fu, Y.; Chen, Y.; Zhu, J.)
Energy & Fuels; (Article); 2004; 18(1); 228-233




indole_amine

indole_amine:
Regio- and Chemoselective Catalytic Transfer Hydrogenation of Aromatic Nitro and Carbonyl as Well as Reductive Cleavage of Azo Compounds over Novel Mesoporous NiMCM-41 Molecular Sieves
(Mohapatra, S. K.; Sonavane, S. U.; Jayaram, R. V.; Selvam, P.)
Org. Lett. 2002; 4(24); 4297-4300




abstract:
Regio- and chemoselective reduction of nitroarenes and carbonyl compounds and reductive cleavage of azo compounds, including bulkier molecules, was achieved by the catalytic transfer hydrogenation method (CTH) using a novel nickel-containing mesoporous silicate (NiMCM-41) molecular sieve catalyst. In addition, the catalyst was also found to behave as a truly heterogeneous catalyst as the yield was practically unaffected.

(also note that they used IPA as the hydrogen donor)

indole_amine

indole_amine:
Clay is a pretty dang cool thing... :)

Preparation of Ultrafine Palladium Particles on Cationic and Anionic Clays, Mediated by Oppositely Charged Surfactants: Catalytic Probes in Hydrogenations
(Z. Király,* B. Veisz, Á. Mastalir, and Gy. Köfaragó)
Langmuir, 17 (17), 5381 -5387, 2001 (!)




Abstract:
Finely divided Pd particles (2-3 nm in diameter) were synthesized by the reduction of Pd2+ precursor ions in the presence of cationic (myristyltrimethylammonium bromide, MTA+Br-) or anionic (sodium dodecyl sulfate, Na+DS-) surfactants. The protective adsorption layer of the ionic surfactants around the particles ensured the long-term stability of the aqueous dispersions. When the palladium hydrosol stabilized with MTA+Br- was mixed with an aqueous suspension of sodium montmorillonite, Na+MM- (a cationic clay), the cation-exchange reaction between Na+ and MTA+ rendered the montmorillonite surface hydrophobic, in parallel with the incorporation of the released Pd particles into the MTA+MM- organoclay host. In a similar way, after addition of the palladium hydrosol stabilized with Na+DS- to an aqueous suspension of hydrotalcite nitrate, HT+NO3- (an anionic clay), the ion exchange between NO3- and DS- resulted in the formation of a hydrophobic clay, HT+DS-, with simultaneous deposition of the released Pd particles onto the clay lamellae. The low-loaded, highly dispersed Pd-organoclay materials displayed extremely high catalytic activities under mild conditions in the liquid-phase hydrogenations of styrene, hex-1-ene, and cyclohexene. Furthermore, the catalysts exhibited high selectivities for the partial hydrogenation of 1-phenyl-1-pentyne to 1-phenyl-cis-1-pentene. These high activities and selectivities were explained in terms of the high degree of dispersion of the Pd particles and the hydrophobic nature of the catalysts.


indole_amine

indole_amine:
Asymmetric Catalytic Hydrogenation. Design of New Ru Catalysts and Chiral Ligands: From Laboratory to Industrial Applications
(Jean-Pierre Genet)
Acc. Chem. Res., 36 (12), 908 -918, 2003
DOI:10.1021/ar020152u S0001-4842(02)00152-8




Abstract:
This account covers the design of Ru catalysts and ligands. Two classes of chiral phosphine ligands are prepared: the electron-rich trans-2,4-substituted phosphetanes, readily available from optically pure 1,3-diol cyclic sulfates, and atropoisomeric ligands (SYNPHOS, MeO-NAPhePHOS, bearing heterotopic biaryl moieties, and a chiral water-soluble diguanidinium binaphthyl diphosphine, Digm-BINAP). Applications of these ligands to rhodium- and ruthenium-mediated hydrogenation of ketones and olefins have been reported with high enantioselectivities. The recognition abilities of Ru-SYNPHOS for a wide range of ketones is superior to those observed with BINAP, MeO-NAPhePHOS, and MeO-BIPHEP. Several biologically active compounds have been prepared through dynamic kinetic resolution. This work gives access to a number of highly active catalysts of the type [Ru(biphosphane)(H)(6-cot)]BF4. These catalysts have demonstrated their utility in the enantioselective hydrogenation of the tetrasubstituted cyclopentenone "dehydrodione", which leads to the commercially important perfume component Paradisone.

..probably interesting if any bee would like to prepare their customized stereoselective hydrogenation catalyst complex? (who knows?  :) )


indole_amine

Dope_Amine:
58.9 g 'tone
3x molar Formic
1.8x molar MeNH3Cl
4x KOH
660 mL MeOH
75 mL H2O
18 g Pd/C (fresh)

3 days stirring in ice water.  Got back 54% in amine, 19% back in 'tone.  She is bummed mainly by the return of 73% total back from the extraction.  The rxn mix was close to a liter in volume.  Pd/C filtered, and 1 L of (100mL HCl +H2O) added, and extraction w/ 100 + 100 mL DCM, followed by basifying to 10->11 w/ 6 M NaOH over the course of extraction with 250 + 200 + 150 + 100 mL DCM.  She, at first considered rotovaping b4 filtration of catalyst, but decided she did not want to heat the rxn mix after having kept it cool for so long.  What she should have done instead was filter the catalyst and then rotovap before adding acid.  Doh!

The product oil was much cleaner without tinting of color. 

If one were to assume 100% extraction recovery of reactants/products at the above mentioned ratio of product:reactant, the product yield would bee 74%.  Not too bad with a 1.8 molar excess of MeNH3Cl.  Definitely could be better though...

She is done with this theoretical laboratory research buzzing in her dreams.

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