Ionic liquids in methyltrioxorhenium catalyzed epoxidation–methanolysis of glycals under homogeneous and heterogeneous conditions

Adaptation of Zemplén's conditions for a simple and highly selective approach to methyl 1,2-trans glycosides

1,2-trans methyl glycosides can be readily obtained from peracetylated sugars through their initial conversion into glycosyl iodide donors and subsequent exposure of these latter to a slight excess of sodium methoxide in methanol. Under these conditions a varied set of mono- and disaccharide precursors afforded the corresponding 1,2-trans glycosides with concomitant de-O-acetylation in satisfying yields (in the range 59-81%). A similar approach also proved effective when using GlcNAc glycosyl chloride as the donor.

Dendrimer crown-ether tethered multi-wall carbon nanotubes support methyltrioxorhenium in the selective oxidation of olefins to epoxides

Benzo-15-crown-5 ether supported on multi-wall carbon nanotubes (MWCNTs) by tethered poly(amidoamine) (PAMAM) dendrimers efficiently coordinated methyltrioxorhenium in the selective oxidation of olefins to epoxides.

Recent developments in β-C-glycosides: synthesis and applications

In the last few years, considerable progress has been made in the synthesis of C-glycosides. Despite its challenging chemistry, due to its versatility, C-glycosides play a pivotal role in developing novel materials, surfactants and bioactive molecules. In this review, we present snapshots of various synthetic methodologies developed for C-glycosides in the recent years and the potential application of C-glycosides derived from β-C-glycosidic ketones.

Methyltrioxorhenium catalysis in nonconventional solvents: a great catalyst in a safe reaction medium

The requirement that chemical processes are sustainable, reflected in waste reduction and the use of safe reagents and reaction conditions, is becoming even more stringent as a result of pressure by society and governments to preserve the environment and protect human health. Catalysis offers numerous benefits related to green chemistry, including lowered energetic reaction requirements; catalytic, rather than stoichiometric, amounts of materials; increased selectivity; lowered consumption of processing and separation agents; and, in many cases, the use of less-toxic compounds. Our research group has for a long time been studying methyltrioxorhenium in the oxyfunctionalization of different substrates, by using H(2)O(2) or its urea-hydrogen peroxide complex as the primary oxidant. In this Review paper we aim to provide a full literature account on the catalytic activity and selectivity of methyltrioxorhenium in the oxyfunctionalization reaction, either in nonconventional solvents or under solvent-free conditions, with a particular emphasis on the use of ionic liquids as green reaction media.