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A systematic in-situ FTIR study on the formation and reaction of adsorbed species in N2O reduction by CH4 over Fe-BEA catalyst is carried out. In effect, it is proposed that N2O plays an important role in the initial steps (reaction with CH4 to form methoxy species) on the selective catalytic reduction (SCR) of N2O with CH4.

Enantioselective α-allylation of α-substituted β-ketoesters with simple allyl alcohols was successfully performed by synergistic catalysis with the catalyst combination of a chiral primary amino acid and an achiral palladium complex without additional promotors like acids or bases. The allylation reaction and generation of a chiral quaternary carbon stereocenter proceeded smoothly to produce α,α-disubstituted β-ketoesters in high yields (91-99%) with high enantioselectivities (90-99% ee). [ABSTRACT FROM AUTHOR]

Direct α-allylation of α-branched aldehydes was successfully carried out with a readily available allyl ester by combined use of two catalytic systems: Tsuji-Trost allylation reaction with an achiral palladium complex and enamine catalysis with a chiral primary α-amino acid. A quaternary carbon stereogenic center was constructed stereoselectively to give various 2,2-disubstituted pent-4-enals in good yields with high enantioselectivity. [ABSTRACT FROM AUTHOR]

For an unbaffled agitated vessel with an angularly oscillating impeller whose rotation continues while periodically reversing its direction at a set angle, the progress of mixing of Newtonian liquid phase was studied experimentally in relation to the impeller power characteristics. Results obtained for the angular oscillation mode of a disk turbine impeller with six flat blades with different amplitudes (Strouhal number) were compared to those obtained for the unidirectional rotation mode of the impeller of identical design. Using an angularly oscillating impeller, turbulent and laminar mixings were effective, respectively, with larger and smaller amplitudes. The mixing characteristics for turbulent and laminar flow regions were discussed on the basis of the flow field features, which the impeller power number reflected. [ABSTRACT FROM AUTHOR]

The article presents information on a study which has demonstrated the utility of the enantioselective organocatalytic amine conjugate addition, which is a highly chemo- and stereo- selective transform founded upon a rationally designed N-centered nucleophile. The utility of this organocatalytic amine addition is presented in the one-pot conversion of simple aldehydes to enantioenriched β-amino acids.