Glycerol, a cheap renewable feedstock, was converted selectively to 1,2-propanediol by heating under low hydrogen pressure (10 bar), in the presence of Raney nickel. No solvents or additives were required, and the product could be distilled out of the reaction mixture. Addition of a phosphonium salt, a liquid at the reaction temperature, improved the selectivity and rate to a small extent but did not facilitate the separation of the final reaction mixture.

Dimethyl carbonate (DMC) is an environmentally sustainable compound which can be used efficiently for the upgrading of several promising renewables including glycerol, triglycerides, fatty acids, polysaccharides, sugar-derived platform molecules and lignin-based phenolic compounds. This review showcases a thorough overview of the main reactions where DMC acts as a methylating and/or methoxycarbonylating agent for the transformation of small bio-based molecules as well as for the synthesis of biopolymers. All processes exemplify genuine green archetypes since they couple innocuous reactants of renewable origin with non-toxic DMC. Each section of the review provides a detailed overview on reaction conditions and scope of the investigated reactions, and discusses the rationale behind the choice of catalyst(s) and the proposed mechanisms. Criticism and comments have been put forward on the pros and cons of the described methods and their perspectives, as well as on those studies which still require follow-ups and more in-depth analyses

The methylating efficiency of dimethyl carbonate (DMC), dimethyl sulfate (DMS), methyl iodide (MeI), and methanol (MeOH) was assessed based on atom economy and mass index. These parameters were calculated for three model reactions: the O-methylation of phenol, the mono-C-methylation of phenylacetonitrile, and the mono-N-methylation of aniline. The analysis was carried out over a total of 33 different procedures selected from the literature. Methanol and, in particular, DMC yielded very favourable mass indexes (in the range 3-6) indicating a significant decrease of the overall flow of materials (reagents, catalysts, solvents, etc.), thereby providing safer greener catalytic reactions with no waste.

The fractal dimension of a macromolecular coil is used for the characterization of a polymeric melt structure. It is shown that the kinetics of oxygen consumption is defined by both the chemical constitution of a polymer and its structure. The quantitative analysis of the kinetical curves of the oxygen consumption in the thermooxidative degradation process was carried out in the framework of the fractal approach. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2378–2381, 2003