Nitrobiphenyls

Ingold and his co-workers used the competitive method in their experiments, in which nitration was brought about in acetic anhydride. Typically, the reaction solutions in these experiments contained o-8-I 4 mol of nitric acid, and the reaction time, depending on the reactivities of the compounds and the temperature, was 0-5-10 h. Results were obtained for the reactivities of toluene, > ethyl benzoate, the halogenobenzenes, ethyl phenyl acetate and benzyl chloride. Some of these and some later results are summarized in table 5.2. Results for the halogenobenzenes and nitrobiphenyls are discussed later ( 9.1.4, lo.i), and those for a series of benzylic compounds in 5,3.4. 

The nitration of phenylpyridines and related compounds has attracted attention for a long time, and measurements of isomer proportions have been made for several compounds of this type. Nitration occurs in the phenyl ring. For 2-phenylpyridine and 2-phenylpyridine i-oxide measurements of the dependence of rate of nitration upon acidity in 75-81 % sulphuric acid at 25 °C show that both compounds are nitrated as their cations (table 8.1). The isomer distribution did not depend significantly upon the acidity, and by comparison with the kinetic data for quinolinium ( 10.4.2) the partial rate factors illustrated below were obtained.They should be compared with those for the nitration of 2-nitrobiphenyl ( 10.1). The protonated heterocyclic groups are much... 

Nitrobiphenyl [86-00-0] M 199.2, m 36.7 . Crystd from EtOH (seeding required). Sublimed under vacuum. 

Fig. 4.58. Raman spectra of nitrophenyl modi- 1336 and 1586 cm" might be affected by sub-fied (A) and untreated (B) glassy carbon, the dif- traction of closely neighboring, much stronger ference between spectra A and B (C), and the re- bands of the carbon bulk. Five further marked ference spectrum of solid 4-nitrobiphenyl (D). surface bands are clearly visible in the difference The strongest surface bands at approximately spectrum C [4.292],...

Phenylbenzofuroxan (22) is formed on pyrolysis or photolysis of 2-azido-3-nitrobiphenyl the alternative mode of cyclization—to 4-nitroearbazole—was not observed. ... 

Amino 2 deoxy d glucose, conversion of hydrochloride to 2 acetamido-2 deoxy d glucose, 46, 2 l-(Ammomcthyl) cycloheptanol, 46, 31 2 Amino 2 methyl 1 propanol in isolation of levopimanc acid 45, 64 c-Amino p nitrobiphenyl, by nitration of o aminobiphenyl, 46, 86 from o,p dimtrobiphenyl, 46, 88 Amino 2 propanone, semicarbazone... 

In DMSO as solvent and in the presence of nitrobenzene, aryl-de-diazoniation of the unsubstituted benzenediazonium ion leads mainly via meta substitution to 3-nitrobiphenyl, whereas in the case of the 4-nitrobenzenediazonium ion the formation of o- and -substituted products (2,4 -and 4,4 -dinitrobiphenyl) prevails (Gloor et al., 1972). 

Salicylic acid analogues are often active as nonsteroidal antiinflammatory agents because they interfere with biosynthesis of prostaglandins. Diflunisal (3) appears to be such an agent. It is synthesized from the nitrobiphenyl 1 by catalytic reduction to... 

B. m-Nitrobiphenyl. To a 5-1. three-necked flask equipped with a sealed mechanical stirrer, a dropping funnel, and a reflux condenser are added 116.4 g. (0.6 mole) of l-(jw-nitrophenyl)-3,3-dimethyltriazene and 2.5 1. of benzene. The benzene solution is heated to maintain refluxing and stirred vigorously while a solution of 148 g. (0.8 mole) of 94% toluenesulfonic acid (Note 7) in 750 ml. of benzene is added dropwise (Note 8) over a period of 4-4.5 hours. The refluxing is continued for 1-1.5 hours (Note 9)... 

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