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Abstract: Semi-domesticated reindeer (Rangifer tarandus tarandus (L., 1758)) is the primary prey of Eurasian lynx (Lynx lynx (L., 1758)) in northern Sweden. The reindeer migrate between winter range in the [...]

The Suzuki cross-coupling reaction is a very efficient, reliable, and environmentally friendly method for the introduction of novel carbon--carbon bonds into molecules. This review summarizes recent advances in the use of the reaction in aqueous media with a focus on different types of ligands and the ligandless protocols currently in use. Several synthetic targets for the reaction have been mentioned. The work summarizes recent results from studies on asymmetric Suzuki reactions performed in organic--aqueous mixed solvents. Key words: Suzuki reaction, green chemistry, metal-catalyzed cross-coupling reactions, aqueous synthesis media.

Metal-catalyzed coupling reactions are very efficient and reliable methods for the introduction of new carbon-carbon bonds onto molecules attached to a solid support. This review summarizes recent advances in utilizing the three most used methods, the Suzuki reaction, the Heck reaction, and the Stille reaction, in the field of solid phase organic synthesis resulting in small organic molecule libraries. Key words: metal-catalyzed coupling reactions, carbon--carbon bonds, solid phase synthesis, combinatorial chemistry, drug discovery.

Softwood chlorination stage liquor obtained from a pulp mill, chlorine-treated natural humic water and drinking water were analyzed for chlorinated enol lactones and cyclopentene-1,3-diones. Both chemicals were formed during the chlorination of softwood pulp and of water with humic material. The amount of unbleached pulp and the chlorine dose influenced the amount of chlorinated enol lactones and cyclopentene-1,3-diones produced.

The qualitative and quantitative measurement of hydroxyfuranones in pulp bleaching liquor, chlorinated humic water and drinking water samples was conducted. The 5-methyl-5-hydroxyfuranones, were also investigated with respect to their mutagenicity in the Ames assay. In addition, their stability characteristics in acidic and neutral solutions were compared and found to be dependent on the degree of chlorine substitution.

The synthesis of hydroxyfuranones with a dichloromethyl, monochloromethyl or methyl group joined to the carbon at the 4-position in the furanone ring and with a chlorine or hydrogen atom attached to the carbon at the 3-position was undertaken. These compounds were quantitatively determined in chlorination-stage bleaching liquors and in extracts of chlorinated fulvic acids, chlorinated humic water and chlorine-purified drinking water. The compounds were found to induce mutagenicity in the Ames tester strain TA100.

The multicomponent Petasis borono-Mannich (PBM) reaction is a useful tool for the preparation of complex molecules in a single step from boronic acids, aldehydes/ketones, and amines. Here, we describe the use of glycerol in the PBM reaction of salicylaldehydes or 2-pyridinecarbaldehyde with several boronic acids and secondary amines. From these readily available starting materials, alkylaminophenols, 2-substituted pyridines, and 2H-chromenes were prepared in reasonable to good yields. Glycerol was compared with other solvents, and in some cases, it provided the reaction product in higher yield. Crude glycerol, as generated by the biodiesel industry, was evaluated and found to be a suitable solvent for the PBM reaction, successfully expanding the potential use of this industry by-product. Based on density functional theory (DFT) calculations and the obtained experimental results, the involvement of glycerol-derived boronic esters in the reaction mechanism is suggested to be competitive with the free boronic acid pathway. Similar Gibbs free energies for the aryl migration from the boronate species to the iminium were determined for both mechanisms. [ABSTRACT FROM AUTHOR]