BACKGROUND The production of value‐added products from biomass has acquired increasing importance due to the high worldwide demand for chemicals and energy, uncertain petroleum availability and the necessity of finding environmentally friendly processes. This paper reports work on the synthesis of several catalysts for the conversion of glucose to methyl lactate. RESULTS A MCM‐41 type mesoporous material containing tin (Si/Sn = 55) was developed with a uniform ordered mesoporous structure, high specific surface area and high pore volume. Sn‐MCM‐41 was tested in three consecutive catalytic cycles to evaluate its reusability giving methyl lactate yields of 43%, 41% and 39%, in each cycle. The slightly reduction in activity could be explained by the reduction in the accessibility of active centers due to the adsorption of reaction products and structural changes. Microporous titanosilicates and MFI‐type zeolite ZSM‐5 showed a lower catalytic performance, but exfoliated materials gave higher yields of methyl lactate and pyruvaldehyde dimethyl acetal than their respective layered precursors. CONCLUSIONS Sn‐MCM‐41 material showed good results in the conversion of glucose to methyl lactate over three catalytic cycles and exfoliated materials facilitated the access of glucose to the catalytic sites and fast desorption of products. © 2013 Society of Chemical Industry

Chiral ordered mesoporous silica (COMS) was synthesized in basic media by combining tetraethyl orthosilicate and quaternized aminosilane (with a templating role) silica sources together with four different standard amino acids (arginine, histidine, isoleucine, and proline). Besides the hexagonal MCM-41-type structure, narrow pore size distribution, and high specific surface area, it was found that these solids have potential for enantiomeric separation because of the transference of chirality from the amino acid to the silica. This is illustrated by the resolution of several racemic mixtures (those of proline, isoleucine, trans-4-hydroxyproline, pipecolic acid, valine, leucine, and phenylglycine) with the calcined COMS prepared with l-proline. The opposite behavior observed in induced circular dichroism experiments with calcined COMS, obtained using both enantiomers of proline, confirmed their chiral nature. The high number and variety of existing amino acids, and chiral organic compounds in general, makes these ordered silicas attractive for the production of enantiopure substances.

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