2974-92-7

Usage

Uses

3,4-Dichlorobiphenyl is a polychlorinated biphenyl (PCB) congeners.

InChI:InChI=1/C12H8Cl2/c13-11-7-6-10(8-12(11)14)9-4-2-1-3-5-9/h1-8H

Upstream product

• 55702-46-0 2,3,4-trichlorobiphenyl 
• 53555-66-1 PCB 38 
• 33284-53-6 PCB 61 
• 95-50-1 1,2-dichloro-benzene 
• 94-36-0 dibenzoyl peroxide 
• 62-53-3 aniline 
• 18282-59-2 4-bromo-1,2-dichlorobenzene 
• 71-43-2 benzene 
• 95-94-3 1,2,4,5-tetrachlorobenzene 

Downstream Products

• 92-52-4 biphenyl 
• 2051-61-8 m-chlorobiphenyl 
• 2051-62-9 4'-biphenyl chloride 
• 51-44-5 3,4-dichlorbenzoic acid 
• 67-64-1 acetone 
• 827-52-1 1-phenyl-1-cyclohexane 
• 24973-50-0 3-phenylbenzonitrile 
• 2920-38-9 4-cyano-1,1'-biphenyl 
• 4128-63-6 biphenyl-3,4-dicarbonitrile 
• 720-75-2 methyl 4-phenylbenzoate 
• 16606-00-1 methyl 3-phenylbenzoate 
• 886969-94-4 methyl 4-chlorobiphenyl-3-carboxylate 

Relevant academic research and scientific papers

Phototransformations of polychlorobiphenyls in brij 58 micellar solutions

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.

Iron(III)-Catalyzed Ortho-Preferred Radical Nucleophilic Alkylation of Electron-Deficient Arenes

The untraditional iron-catalyzed, ortho-preferred, radical alkylation of electron-deficient (hetero)arenes is reported. A variety of electron-deficient arenes were shown to react with various primary alkyl sources, producing the alkylated (hetero)arenes in good yields. This reaction might be an alkyl radical, nucleophilic aromatic substitution reaction, rather than the traditional electrophilic Friedel-Crafts reaction. HOMO-LUMO analysis and DFT studies on the key transition states underlying the regioselectivity are consistent with the observed reactions and the conclusions.

K-10 montmorillonite-catalyzed solid phase diazotizations: Environmentally benign coupling of diazonium salts with aromatic hydrocarbons to biaryls

A new heterogeneous catalytic diazotization and subsequent coupling of diazonium salts with aromatics for the synthesis of biaryls is described. The method involves the solid phase diazotization of anilines and the successive C-C bond formation of the diazonium salt with alkylbenzenes. Excellent yields were obtained for a broad range of anilines and aromatic nucleophiles. The reaction was carried out using K-10 montmorillonite as an acid catalyst and medium as well. The high selectivity, metal-free, recyclable catalyst, easy work up, and absence of harmful waste make the process a sustainable alternative to available methods.

Polychlorinated biphenyl reductive dechlorination by vitamin B12s: Thermodynamics and regiospecificity

Microbial reductive dechlorination reactions play an important role in determining the environmental fate of polychlorinated biphenyls (PCBs), especially for PCB congeners with more than four chlorines. Powerful chemical catalysts such as vitamin B12s provide an effective tool for the study of reductive dechlorination reactions. The reductive dechlorination of PCBs by titanium(III) citrate-reduced vitamin B12s was studied in batch reactors. Long-term experiments demonstrated reductive dechlorination of aqueous and sediment-sorbed 2,3,4,5,6-pentachlorobiphenyl (2,3,4,5,6-PeCB) to tetra-, tri-, di-, and monochlorobiphenyl products. Approximately 10% chlorine removal was observed in 36 days in aqueous experiments at 20°C; the sediment experiment showed 40% chlorine removal in 42 days at 30°C. Nearly all possible intermediates were produced and reductively dechlorinated, with no apparent accumulation of individual congeners. Short-term experiments were conducted to determine the pathway forvitamin B12s-catalyzed reductive dechlorination of aqueous 2,3,4,5,6-PeCB and its dechlorinated products; relative product distributions were measured for all possible tetra-and trichlorobiphenyl reductive dechlorination reactions. Theoretical product distributions based on free energies of formation agreed with observed product distributions for short-and long-term experiments. Reductive dechlorination was favored at positions with adjacent chlorines; on average, chlorines were removed equally from ortho, meta, and para positions.

Hydrogenolysis of polychlorinated biphenyls by sodium borohydride with homogeneous and heterogeneous nickel catalysts

The hydrogenolysis (hydrodechlorination) of a series of pure PCB congeners with sodium borohydride was studied. In the absence of nickel compounds, very little reaction occurred, but in the presence of solid Raney-type nickel or in the presence of a soluble Ni(0)triphenylphosphine complex, extensive hydrogenolysis occurred at ambient temperatures in DMF. The selectivity of one congener versus another was studied and found to be low. The selectivity for 2-, 3-, and 4-chloro displacement from di- and trichlorobiphenyls in the presence of Ni(0) complexes, however, was found to be high. The selectivities are interpreted with respect to the known mechanism of oxidative addition of aryl halides with Ni(0) complexes.