The hydrodeoxygenation (HDO) of maize oil was performed in an autoclave with Mo‐based catalysts supported by different carbon materials, such as reduced graphene oxide, activated charcoal, graphite, and fullerene. Nanostructured Mo‐based catalysts with different phase compositions were prepared by using the carbothermal hydrogen reduction method at temperatures ranging from 500 to 700 °C and characterized by Raman spectroscopy, N2 adsorption isotherms, SEM, TEM, XRD, X‐ray photoelectron spectroscopy, and ammonia temperature‐programmed desorption. The highest total hydrocarbon yield of 90.32 % was obtained on the reduced graphene oxide‐supported molybdenum carbide catalyst at 700 °C. These results are subject to the complicated effect of different factors such as phase composition, defect concentration, and particle size on the catalytic behavior of the materials. Unique structures of different supports also play a significant role in the HDO reaction. On the basis of the results of comprehensive analysis of products and catalysts, an HDO mechanism was proposed. These Mo‐based catalysts are a promising system to prepare high‐quality diesel fuels from renewable resources.

A series of novel N,O-psiconucleosides has been prepared in both enantiomeric forms by resolution of an advanced racemic synthetic intermediate using (R)-N-phenylpantolactam as a chiral resolution agent. The absolute configuration of all of these compounds has been unequivocally established by chemical correlation with the novel (R)- or (S)-1-methyl-5-phenylpyrrolidine-2,3-dione, prepared from the known (R)- and (S)-1-methyl-5-phenylpyrrolidin-2-one, respectively.

ABSTRACT:Four new phosphorus dendrimeric phase-transfer catalysts are prepared containing on the surface twelve (+)-cinchoninium salts, obtained by quaternisation of the quinuclidinic nitrogen. Asymmetric alkylation of a glycinate Schiff base with benzyl bromide is used as a benchmark reaction, showing that the more active dendrimeric catalyst is the one containing an allyl group on the O-9 hydroxy group of the cinchonine units. The recovery and reuse of the catalyst are possible for five consecutive runs without loss of activity and slight decrease in enantioselectivity. When other electrophiles are used, substituted benzyl bromides give better results than other activated alkyl bromides affording the corresponding (R)-amino acids derivatives. Comparison of these results with the ones previously reported for similar cinchoninium salts, shows that dendrimers could be a better support than other polymers for this type of organocatalysis.

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