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A novel synthesis strategy to access 2-alkoxyquinoline derivatives via a palladium-driven cascade reaction is disclosed. Unlike classic methods based on the alkylation of 2-quinolones with alkyl halides, the present method benefits from the de novo assembly of the quinoline core starting from 1,3-butadiynamides. Palladium-catalyzed reaction cascades with N-(2-iodophenyl)-N-tosyl-1,3-butadiynamides and primary alcohols as external nucleophiles proceed under mild reaction conditions and selectively deliver a variety of differently functionalized 4-alkenyl 2-alkoxyquinolines in a single batch transformation. [ABSTRACT FROM AUTHOR]

Suspended particulate matter (SPM), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCP) were studied in the snow cover at urban and suburban localities in the Irkutsk region, Eastern Siberia for their temporal variations in 2009–2023, daily deposition fluxes (DDFs), and effects of some meteorological factors, as well as the effects of different technogenic activities in the industrial area of the former organochlorine enterprises of Usol'ekhimprom. SPM loads at both stations were found to be at a low level of pollution. The levels of HCB, α + γ-HCH, and ∑p,p′-DDX were lower than Russian maximum permissible levels (MPLs) in drinking water, groundwater, and surface water for household drinking and cultural purposes. The sums of all organochlorine compounds studied in snow were higher than the MPL in freshwater water bodies for fishery purposes. The levels of the DDFs of HCHs, DDTs, and heptachlorinated PCB decreased, di- and trichlorinated PCB levels increased, and HCB levels changed at a polynomial line during 2009–2023. The change in the relative composition of PCBs was found as a result of recultivation activities at the industrial area of the former organochlorine enterprise of Usol'ekhimprom. The air humidity and temperature are the key meteorological factors affecting the DDFs of PCBs and OCPs. [ABSTRACT FROM AUTHOR]

The freshwater Lake Baikal, a UNESCO World Heritage Site, has a unique ecosystem threatened by PCB and PCDD/F contamination. Analysis of fish and soil samples show the chemicals are low in the pristine northeast area and high in the southwest industrialized area, which includes a chloralkali chemical complex.

Despite the wide spread of computing devices and mathematical optimization methods in various fields of knowledge, little attention is paid to optimization of solving the problems of labor safety. In the author's opinion the promising solution is developing the methods of sound-absorbing cover optimization based on non-linear programming, one of which has been the objective of the work. The method for estimation of the optimal cover in premises with multi-tone noise conditions is proposed in the paper. Different noise tones can be absorbed by different materials with the most suitable properties. The method is based on random selection of surface area values of different materials, with further selection of the optimal cover. The paper gives the estimation algorithm and the obtained results using the Mathcad computer program. The estimation results indicate the regularities of achieving the optimum and a significant economic effect. The proposed estimation method and algorithm can be used for taking labor safety measures for noise reduction, namely, sound-absorbing covers design for production facilities. The paper has a scientific novelty, based on random selection of materials surface area values, and practical significance based on economic effect and working conditions improvement. [ABSTRACT FROM AUTHOR]