55720-44-0Relevant articles and documents
Synthesis of chlorinated biphenyls by Suzuki cross-coupling using diamine or diimine-palladium complexes
Kylmaelae, Tuula,Kuuloja, Noora,Xu, Youjun,Rissanen, Kari,Franzen, Robert
experimental part, p. 4019 - 4024 (2009/04/11)
Several novel diimines (Salen-type ligands) 2a-2i and their reduced diamine counterparts 3b,3d-3g and 3i form complexes 4a-4i, 5b,5d-5g, and 5i with PdCl2 in DMF or methanol. Using 1 mol-% of the isolated complexes 4e and 5f many polychlorinated biphenyls (PCBs) can be prepared in moderate to excellent yields according to the Suzuki cross-coupling protocol with contact to air. Several 4-acetylbiphenyls prepared by this method can be converted in moderate yields into the corresponding biphenylcarboxylic acids (BCAs) by alkaline cleavage. An X-ray crystal structure determination confirms the structure of complex 5f. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
Phototransformations of polychlorobiphenyls in brij 58 micellar solutions
Chu, Wei,Jafvert, Chad T.,Diehl, Claude A.,Marley, Karen,Larson, Richard A.
, p. 1989 - 1993 (2007/10/03)
Our purpose in conducting these studies was to examine photolysis as a destructive process for polychlorobiphenyls (PCBs) extracted from soils with surfactant solutions. Surfactants have shown promise as agents for removing free phase and sorbed contaminants from soils, yet information on ultimate disposal options and recycle/recovery strategies for the surfactants is generally lacking. For arylhalides, photodechlorination may result in decontamination, eliminating the need to physically separate these contaminants from the washing solution. Photochemical reactions of the PCB congener mixture, Aroclor 1254, and the specific congener, 2,3,4,5- tetrachlorobiphenyl (2,3,4,5-TeCB), were investigated in aqueous solutions containing surfactant micelles with UV light at 253.7 nm. Photoreduction through photodechlorination was shown to be the main decay pathway in which lesser chlorinated congeners were formed as intermediates. In experiments with 2,3,4,5-TeCB, final noncarbon-containing products included Cl- and H+, both produced nearly stoichiometrically from the starting materials. The quantum yield for decay of 0.1 μM 2,3,4,5-TeCB in 0.5 mM Brij 58 micellar solutions was over six times greater than in water alone. Sequential extraction from a soil and photoreduction of 2,3,4,5-tetrachlorobiphenyl by Brij 58 solutions proved to be limited by surfactant loss to the soil. Our purpose in conducting these studies was to examine photolysis as a destructive process for polychlorobiphenyls (PCBs) extracted from soils with surfactant solutions. Surfactants have shown promise as agents for removing free phase and sorbed contaminants from soils, yet information on ultimate disposal options and recycle/recovery strategies for the surfactants is generally lacking. For arylhalides, photodechlorination may result in decontamination, eliminating the need to physically separate these contaminants from the washing solution. Photochemical reactions of the PCB congener mixture, Aroclor 1254, and the specific congener, 2,3,4,5-tetrachlorobiphenyl (2,3,4,5-TeCB), were investigated in aqueous solutions containing surfactant micelles with UV light at 253.7 nm. Photoreduction through photodechlorination was shown to be the main decay pathway in which lesser chlorinated congeners were formed as intermediates. In experiments with 2,3,4,5-TeCB, final noncarbon-containing products included Cl- and H+, both produced nearly stoichiometrically from the starting materials. The quantum yield for decay of 0.1 μM 2,3,4,5-TeCB in 0.5 mM Brij 58 micellar solutions was over six times greater than in water alone. Sequential extraction from a soil and photoreduction of 2,3,4,5-tetrachlorobiphenyl by Brij 58 solutions proved to be limited by surfactant loss to the soil.
Photoreactions of polyhalobenzenes in benzene. Formation of terphenyls
Nakada,Miura,Nishiyama,Higashi,Mori,Hirota,Ishii
, p. 3122 - 3126 (2007/10/02)
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