An efficient chlorination of aromatic compounds using a catalytic amount of iodobenzene

An efficient method was developed for chlorination of aromatic compounds with electron-donating groups using iodobenzene as the catalyst and m-chloroperbenzoic acid as the terminal oxidant in the presence of 4-methylbenzenesulfonic acid in THF at room temperature for 24 h,and a series of the monochlorinated compounds was obtained in good yields.In this protocol,the catalyst iodobenzene was first oxidized into the hypervalent iodine intermediate,which then treated with lithium chloride and finally reacted with aromatic compounds to form the chlorinated compounds.

Gas-phase catalytic hydration of I_(2)O_(5) in the polluted coastal regions:Reaction mechanisms and atmospheric implications

Marine aerosols play an important role in the global aerosol system.In polluted coastal regions,ultra-fine particles have been recognized to be related to iodine-containing species and is more serious due to the impact of atmospheric pollutants.Many previous studies have identified iodine pentoxide(I_(2)O_(5),IP)to be the key species in new particles formation(NPF)in marine regions,but the role of IP in the polluted coastal atmosphere is far to be fully understood.Considering the high humidity and concentrations of pollutants in the polluted coastal regions,the gas-phase hydration of IP catalyzed by sulfuric acid(SA),nitric acid(NA),dimethylamine(DMA),and ammonia(A)have been investigated at DLPNO-CCSD(T)//ωB97 XD/aug-cc-pVTZ+aug-cc-pVTZ-PP with ECP28 MDF(for iodine)level of theory.The results show that the hydration of IP involves a significant energy barrier of 22.33 kcal/mol,while the pollutants SA,NA,DMA,and A all could catalyze the hydration of IP.Especially,with SA and DMA as catalysts,the hydration reactions of IP present extremely low barriers and high rate constants.It is suggested that IP is unstable under the catalysis of SA and DMA to generate iodic acid,which is the key component in NPF in marine regions.Thus,the catalytic hydration of IP is very likely to trigger the formation of iodine-containing particles.Our research provides a clear picture of the catalytic hydration of IP as well as theoretical guidance for NPF in the polluted coastal atmosphere.