The transformation of cellulose or cellulose-derived carbohydrates into platform chemicals is the key to establish biomass-based sustainable chemical processes. The systems able to catalyze the conversion of cellulose into key chemicals in water without the consumption of hydrogen are limited. We report that simple vanadyl (VO(2+)) cations catalyze the conversions of cellulose and its monomer, glucose, into lactic acid and formic acid in water. We have discovered an interesting shift of the major product from formic acid to lactic acid on switching the reaction atmosphere from oxygen to nitrogen. Our studies suggest that VO(2+) catalyzes the isomerization of glucose to fructose, the retro-aldol fragmentation of fructose to two trioses, and the isomerization of trioses, which leads to the formation of lactic acid under anaerobic conditions. The oxidative cleavage of C-C bonds in the intermediates caused by the redox conversion of VO2(+)/VO(2+) under aerobic conditions results in formic acid and CO2. We demonstrate that the addition of an alcohol suppresses the formation of CO2 and enhances the formic acid yield significantly to 70-75 %.

Novel chiral cobalt complexes containing aP NNP-type ligand were synthesized using as traightforward method. The structureso ft he cobalt complexes have been fully characterizedb yX -ray crystallography, high resolution mass spectrometry (HRMS), and electron paramagnetic resonance (EPR). Using H 2 as the hydrogen source, the cobalt-catalyzed asymmetric hydrogenation of various ketones was investigated, and the corresponding chiral alcohols were afforded with up to 99 %y ield and 95 % ee.T ot he best of our knowledge, this is the first example of ac obalt-catalyzed enantioselective hydrogenation of ketones with molecular hydrogen.Scheme1.Synthesis of novel chiral cobalt complexes.

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This paper definitely reveals that LaPO 4 :Ce 31 , Tb 31 (LAP) nanophosphors prepared by normal hydrothermal method suffer significant loss of luminescence due to the oxidation of Ce 31 -Ce 41 at hydrothermal stage. To effectively protect Ce 31 from oxidation, a reductive hydrothermal process using hydrazine hydrate as a protecting agent is proposed to synthesize LAP nanophosphors with different Ce 31 and Tb 31 concentrations, which exhibited much stronger green photoluminescence (PL) and longer lifetime than the products prepared by normal hydrothermal method. Furthermore, the high-brightness LAP nanophosphors exhibited high-quenching concentration of Tb 31 ; the La 0.4 Ce 0.4 Tb 0.2 PO 4 nanophosphor showed almost the same PL intensity as that of the commercially used La 0.7 Ce 0.2 Tb 0.1 PO 4 bulk powder.