O Chloronitrobenzene

Place 50 g. of o-chloronitrobenzene and 75 g. of clean dry sand in a 250 ml. flask equipped with a mechanical stirrer. Heat the mixture in an oil or fusible metal bath to 215-225° and add, during 40 minutes, 50 g. of copper bronze or, better, of activated copper bronze (Section 11,50, 4) (1), Maintain the temperature at 215-225° for a further 90 minutes and stir continuously. Pour the hot mixture into a Pyrex beaker containing 125 g. of sand and stir until small lumps are formed if the reaction mixture is allowed to cool in the flask, it will set to a hard mass, which can only be removed by breaking the flask. Break up the small lumps by powdering in a mortar, and boil them for 10 minutes with two 400 ml. 

The experimental conditions for conducting the above reaction in the presence of dimethylformamide as a solvent are as follows. In a 250 ml. three-necked flask, equipped with a reflux condenser and a tantalum wire Hershberg-type stirrer, place 20 g. of o-chloronitrobenzene and 100 ml. of diinethylform-amide (dried over anhydrous calcium sulphate). Heat the solution to reflux and add 20 g. of activated copper bronze in one portion. Heat under reflux for 4 hours, add another 20 g. portion of copper powder, and continue refluxing for a second 4-hour period. Allow to cool, pour the reaction mixture into 2 litres of water, and filter with suction. Extract the solids with three 200 ml. portions of boiling ethanol alternatively, use 300 ml. of ethanol in a Soxhlet apparatus. Isolate the 2 2- dinitrodiphenyl from the alcoholic extracts as described above the 3ueld of product, m.p. 124-125°, is 11 - 5 g. 

Table 9.7 contains recent data on the nitration of polychlorobenzenes in sulphuric acid. The data continue the development seen with the diehlorobenzenes. The introduetion of more substituents into these deactivated systems has a smaller effect than predicted. Whereas the -position in ehlorobenzene is four times less reactive than a position in benzene, the remaining position in pentachlorobenzene is about four times more reactive than a position in 1,3,4,5-tetraehlorobenzene. The chloro substituent thus activates nitration, a circumstance recalling the faet that o-chloronitrobenzene is more reactive than nitrobenzene. As can be seen from table 9.7, the additivity prineiple does not work very well with these compounds, underestimating the rate of reaction of pentachlorobenzene by a factor of nearly 250, though the failure is not so marked in the other cases, especially viewed in the circumstance of the wide range of reactivities covered. 

In certain cases, alkanolamines function as reduciag agents. For example, monoethanolamine reduces anthraquiaone to anthranols, acetone to 2-propanol, and azobenzene to aniline (17). The reduction reaction depends on the decomposition of the alkan olamine iato ammonia and an aldehyde. Sinulady, diethan olamine converts o-chloronitrobenzene to 2,2 -dichloroazobenzene and y -dinitrobenzene to 3,3 -diamiQoazobenzene. 

Nucleophilic aromatic substitution occurs only if the aromatic ring has an electron-withdrawing substituent in a position ortho or para to the leaving group. The more such substituents there are, the faster the reaction. As shown in Figure 16.18, only ortho and para electron-withdrawing substituents stabilize the anion intermediate through resonance a meta substituent offers no such resonance stabilization. Thus, p-ch oronitrobenzene and o-chloronitrobenzene react with hydroxide ion at 130 °C to yield substitution products, but m-chloronitrobenzene is inert to OH-. 

In a i-l. flask equipped with a mechanical stirrer are placed 200 g. (1.27 moles) of o-chloronitrobenzene and 300 g. of clean... 

Dinitrobiphenyl has been prepared by the action of copper on o-chloronitrobenzene or 0-bromonitrobenzene,2 and on diazotized 0-nitroaniline.3... 

TRINITROBENZENE m-DIBROMOBENZENE m-CHLORONITROBENZENE o-CHLORONITROBENZENE p-CHLORONITROBENZENE tn-D I CHLOROBENZENE o-DICHLOROBENZENE p-DI CHLOROBENZENE m-DIFLUOROBENZENE o-DIFLUOROBENZENE p-DIFLUOROBENZENE m-DI NITROBENZENE o-DINITROBENZENE p-DINITROBENZENE BROMOBENZENE MONOCHLOROBENZENE m-CHLOROPHENOL o-CHLOROPHENOL p-CHLOROPHENOL... 

E., Hu, W., and Ni, L. (2005) Selechve adsorphon of p-chloronihobenzene from aqueous mixture of p-chloroni-trobenzene and o-chloronitrobenzene using HZSM-5 zeolite. Water Res., 39, 1174. 

Source Synthesized from o-chloronitrobenzene in the presence of NaOH and zinc dust (Shriner et ah, 1978). 

Hydracrylic acid, see p-Propiolactone Hydrazobenzene, see Aniline Hydriodic acid, see Methyl iodide Hydrobromic acid, see Bromodichloromethane, Bromoform, Methyl bromide, Metobromuron Hydrochloric acid, see Alachlor. Aldrin, Benzyl chloride, a-BHC, p-BHC, Bis (2-chloroethyl) ether, Bis(2-chloroisopropyl) ether, Bromacil. Bromodichloromethane, Carbon tetrachloride, Chloroethane, Chloroform, o-Chloronitrobenzene. Chloropicrin, Chloroprene, p-Chloronitrobenzene, 2,4-D, see Dalanon-sodium. p.p -DDD, p,p -DDT, Dicamba. 1,1-Dichloroethane, 1,1-Dichloroethylene, fratts-l,2-Dichloroethylene, s/m-Dichloromethyl ether, 2.3-Dichloronitrobenzene. 3.4-Dichloronitrobenzene. 1,2-Dichloropropane, cis-1,3-... 

Nitric acid, see 1-Butene, o-Chloronitrobenzene. p-Chloronitrobenzene, Chloropicrin, 2,3-Dichloronitrobenzene. 3.4-Dichloronitrobenzene. 2,4-Dinitrophenol, Formaldehyde, Isopropylbenzene, Methanol, Methyl mercaptan, 2-Methylphenol, 2-Methylpropene, Methyl sulfide. Nitrobenzene, 2-Nitrophenol, 4-Nitrophenol,... 

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