Biphenyl 4,4 -dinitro

The nitration of nitro- and dinitro-biphenyls has been examined by several workers. i - As would be expected, nitration of the nitro-biphenyls occurs in the phenyl ring. Like a phenyl group, a nitrophenyl group is 0 -directing, but like certain substituents of the type CH CHA ( 9.1.6) it is, except in the case of w-nitrophenyl, deactivating. Partial rate factors for the nitration at o °C of biphenyl and the nitro-biphenyls with solutions prepared from nitric acid and acetic anhydride are given below. The high o p-v2X o found for nitration of biphenyl... 

Alkylphenols, ammonia, asbestos, chlorinated paraffins, 4-chloroaniline, cyanide, detergents, di- -butyl phthalate, polyaromatic hydrocarbons (PAHs e.g. anthracene, benzopyrene, methylcholanthrene, /i-naphthoflavone), nitrate, nitrite, petroleum oil, phenol, pentachlorophenol, 4-nitrophenol, dinitro-o-cresol, polychlorinated biphenyls (PCBs especially coplanar), polychlorinated dioxins, polybrominated naphthalenes, /i-sitosterol, sulfide, thiourea, urea, acid water, coal dust... 

Hetero-substituted 4,7-diarj lbenzofuroxans (Section V,C) are known. The only representative 5-arylbenzofuroxan in Table I is 5,5 -bisbenzofuroxanyl (23), prepared from 4,4 -diamino-3,3 -dinitro-biphenyl by oxidation with hypochlorite. 

Benz -fc]-cinnolin Zuciner Losung von 3 g (0,079 Mol)Lithiumalanatin 15 ml abs. Diathylather wird unter Stickstoff und unter Riihren eine Losung von 4 g (0,0164 Mo]) 2,2 -Dinitro-biphenyl in 35 mi abs. Benzol ge-tropft. Man erhitzt 4 Stdn. unter Ruckflufi, kiihlt ab, versetzt mit 5 ml Wasser, filtriert, wascht das Filtrat und trocknet mit Natriumsulfat. Die organ. Losung wird eingeengt und der Riickstand aus Benzol umkristallisiert ... 

Aus 2,2 -Dinitro-biphenyl erhalt man mit Natriumboranat in Dimethylsulfoxid 79% d.Th. 2,2 -Dinitroso-bi-pkenyP. 

Analog wird 6,6 -Dinitro-2 -formyl-2-carboxy-formyl-biphenyl cyclisiert ... 

Die kathodische Cyclisierung von 2,2 -Dinitro-biphenyl zu Benzo-[c]-cinnolin verlauft anBlei-Kathodcnin Natronlauge nahezu quantitativ1 ebenso leicht bilden sich 3,8-disub-stituierte Bcnzo-[c]-cinnoline2 ... 

Dimethylamino-methyl)-2-hydroxymethyl-aus 2 -Carboxy-2-(dimethylaminocarbonyl)-biphenyl und Lithiumalanat 165 2,2 -Dinitro- 474, 476, 695 6,6 -Dinitro-2,2 -bis-[chlorcarbonyl]- 188 2,2 -Dinitro-4,4 -bis-[diathylamino]- 695 4,4 -Dinitro-2,2 -bis-rhydroxymethyl]- 213 6,6 -Dinitro-2,2 -bis-[hydroxymethyl]- 188 2,2 -Dinitro-4,4 -diamino- 695 6,6 -Dinitro-2,2 -diformyl- 694 4,4 -Dinitro-2,2 -dimethoxycarbonyl- 213 2,2 -Dinitro-4,4 -dimethyl- 695 6,6 -Dinitro-2 -formyl-2-carboxy- 694 2,2 -Dinitroso- 476 -4-hydroxamsaure-chlorid 537 4-(a-Hydroxy-benzyl)- 542 Methoxy- 678 2-Methyl- 556 Nitro- 672, 678 4-Nitro- 687... 

HjCO C3-°H / 4-Hydroxy-4 -methoxy-3-nitro-biphenyl (77) + 2J-Dinitro-4-hydroxy-4 -metkoxy-... (23) 84... 

The isomer 3,5-dinitro-4-methy 1 amino-biphenyl is described in Beil 12,[762] and the isomer 3,4 -dinitro-4-amino-biphenyl-methane in... 

N.N-Dimethylaminobiphenyl and derivs 5 D1308 3,4 -dinitro-4-dimethylaminobiphenyl 5 D1308 2,6,2, 4 -tetranitro-NJN-dimethyl-p-amino-biphenyl 5 D1308... 

Synthetically useful routes to dibenzo[c,e J[l,2]dithiins are normally based on cyclizations of biphenyI-2,2 -disulfonyl chlorides. A method applied successfully to the parent compound reduces the precursor with zinc in acetic acid to generate the bis thiol, which is then gently oxidized to the dithiin using iron(II) chloride (66HC(21-2)952). An alternative one-step reductive cyclization, which has been applied to the preparation of the 2,9- and 3,8-dinitro derivatives, involves reduction of the appropriate bis sulfonyl chlorides with hydriodic acid in acetic acid (68MI22600). Yet another reductive cyclization uses sodium sulfite followed by acidification, and these conditions lead to dibenzo[c,e][1,2]dithiin 5,5-dioxide. The first step of the reaction is reduction to the disodium salt of biphenyl-2,2 -disulfinic acid which, on acidification, forms the anhydride, i.e. dibenzo[c,e][l,2]dithiin 5,5,6-trioxide. This is not isolated, but is reduced by the medium to the 5,5-dioxide (77JOC3265). Derivatives of dibenzo[c,e] [1,2]dithiin in oxidation states other than those mentioned here are obtainable by appropriate oxidation or reduction reactions (see Section 2.26.3.1.4). 

JChimPhys 46,469(1949) CA 44,4298(1950) Dinitro-bixylyl or Dinitro-ftetramethy/ biphenyl),... 

The stabilized diazohium salt procedure has given 3,4 -dinitrobiphenyl (V) in 54% yield from m-mtroaniline and -nitrobenzene and 4,4 -dinitro-biphenyl (VI) in 69% yield from p-nitroaniline and nitrobenzene. 

Biphenyl 3,3 -Dinitro- X/3, 162 2H-Chromon 7-Acetoxy-4-diazomethyl- E14b, 1025 (Sulfonylhydrazon/Base)... 

Biphenyl 2,5-Dinitro-4-hydroxy-4 -methoxy- E16d, 301 (Nitrierung)... 

A mixture of 8 g. (0.032 mole) of p-iodonitrobenzene (p. 184) and 6 g. (0.095 gram atom) of copper powder is heated in an oil bath. Reaction starts at a temperature of 220°, and the color of the mixture changes to brown. The bath temperature is raised slowly to 235°, at which point the reaction is complete. The cooled mass is extracted with portions of boiling toluene until the liquid extract is not colored yellow. The combined toluene extracts are treated with activated carbon and evaporated to a small volume and cooled. 4,4 -Dinitro-biphenyl precipitates in 52% yield as yellow needles melting at 237°. 

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