In order to study the polar substituent effect almost with no steric effect in organophosphorus chemistry,a series of 4-substituted-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-oxides(1)and p-substituted phenylphospho...In order to study the polar substituent effect almost with no steric effect in organophosphorus chemistry,a series of 4-substituted-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-oxides(1)and p-substituted phenylphosphonates(2)and corresponding mono hexyl esters(3)as model were synthesized.^(31)P-NMR chemical shifts of compounds(1)in methanol and deuterioacetone were determined.The Δδ values reflect 4-sbstituent po- lar effect.The ^(31)P-NMR of compounds(2)and(3)and the pKa of compounds(3)were also measured.The results showed that the trend of polar effects of substituents in both carboxylic and organophosphates chemistry are similar,and the change of polar effects in variation with the alkyl groups is not significant.展开更多
Polar regions are free from major anthropogenic impact due to their remoteness. However, certain pollutants can be transported there via atmospheric and/or oceanic circulations. Here we present an overview of current ...Polar regions are free from major anthropogenic impact due to their remoteness. However, certain pollutants can be transported there via atmospheric and/or oceanic circulations. Here we present an overview of current research on organophosphorus esters （OPEs） in polar regions by reviewing the literature on distribution, source and transport of OPEs. Current research on OPEs reveals significant anthropogenic influences in both polar regions. As well as the expected occurrence in the Arctic, OPEs were found on the Antarctic lee Sheet up to 650 km from the coast, and the OPE concentrations were higher at high elevation due to cold climate retention. The immediate source of OPEs for inland Antarctica might be the Southern Ocean surrounding the continent, where OPEs in aerosols and seawater showed comparable concentrations to remote areas in the European Arctic. A positive correlation between aerosol OPEs in the open water and the surface vortex of ocean currents indicates that these compounds may be transported and accumulated in the ocean currents. The Antarctica Circumpolar Current accumulates them in the marginal seas of Antarctica.展开更多
基金Project Supported by National Science Foundation of China.
文摘In order to study the polar substituent effect almost with no steric effect in organophosphorus chemistry,a series of 4-substituted-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-oxides(1)and p-substituted phenylphosphonates(2)and corresponding mono hexyl esters(3)as model were synthesized.^(31)P-NMR chemical shifts of compounds(1)in methanol and deuterioacetone were determined.The Δδ values reflect 4-sbstituent po- lar effect.The ^(31)P-NMR of compounds(2)and(3)and the pKa of compounds(3)were also measured.The results showed that the trend of polar effects of substituents in both carboxylic and organophosphates chemistry are similar,and the change of polar effects in variation with the alkyl groups is not significant.
基金supported by the Chinese Arctic and Antarctic Administration (Grant no.CHINARE2012-2017)the National Natural Science Foundation of China (NSFC) (Grant nos.41306198 and U1407135)the Fundamental Research Funds for the Central Universities (Grant no.wk2080000091)
文摘Polar regions are free from major anthropogenic impact due to their remoteness. However, certain pollutants can be transported there via atmospheric and/or oceanic circulations. Here we present an overview of current research on organophosphorus esters （OPEs） in polar regions by reviewing the literature on distribution, source and transport of OPEs. Current research on OPEs reveals significant anthropogenic influences in both polar regions. As well as the expected occurrence in the Arctic, OPEs were found on the Antarctic lee Sheet up to 650 km from the coast, and the OPE concentrations were higher at high elevation due to cold climate retention. The immediate source of OPEs for inland Antarctica might be the Southern Ocean surrounding the continent, where OPEs in aerosols and seawater showed comparable concentrations to remote areas in the European Arctic. A positive correlation between aerosol OPEs in the open water and the surface vortex of ocean currents indicates that these compounds may be transported and accumulated in the ocean currents. The Antarctica Circumpolar Current accumulates them in the marginal seas of Antarctica.
