4-bromophenyl 3-nitrophenyl

Dichlorophenyl, 692 2-Bromophenyl, 692 4-Nitrophenyl, 692 3,5-Dinitrophenyl, 692 4-Chloro-2-nitrophenyl, 693 2-Chloro-4-triphenylmethylphenyl, 693 2-Methoxy-5-nitrophenyl, 693... 

Ph) has been reported to proceed smoothly to give, as expected, the corresponding 3-Cp-nitrophenyl) and 3-(p-bromophenyl) derivatives. Gibson found that the betaine (132, R = Me) dissolved in sulfuric acid to give a blue solution, a result which is consistent with sulfonation in the naphthalene ring system, and also reported that the same compound reacted smoothly with bromine in acetic acid to give a tetrabromo derivative in which all the bromine atoms were located in the naphthalene system. The structure of this compound was not, however, established. ... 

Problem 18.62 Synthesize from benzene, toluene, naphthalene (NpH), and any aliphatic or inorganic compounds (a) a-(p-nitrophenyl)ethylamine, (b) -(p-bromophenyl)ethylamine, (c) l-(a-aminomethyl) naphthalene, (d) 2-naphthylamine, (e) -NpCH2NH2. 

Studies of the nitration of 4-chloromethyl-2-phenylthiazole have shown that the action of nitric acid (d 1.40) in sulfuric acid at 60°C gives the 4-nitrophenyl product and the use of nitric acid in acetic anhydride at 60°C forms the 5-nitrothiazole product. Chlorination and bromination also result in 5-substitution in the thiazole ring and nitration of these products using mixed acid gives the 4-nitrophenyl products. 2-(4-Bromophenyl)-4-chloromethylthiazole also nitrates at the 5-position of the thiazole ring using nitric acid in acetic anhydride below 60°C (65CB3446). 

A solution of benzamidine hydrochloride dihydrate (48 g, 0.25 mol) in water (100 ml) is added to a solution of a-bromopropiophenone (53 g, 0.25 mol) in chloroform (250 ml) to form a two-phase mixture. While stirring vigorously at room temperature, a solution of KOH (28 g, 0.5 mol) in water (100 ml) is added dropwise, then heated to boiling and refluxed (3-4h). The chloroform phase is then separated from the hot aqueous phase and cooled. Tlie ciwstalline material which separates is washed with benzene, then with diethyl ether to give the above product (which may separate as an oil, but which solidifies gradually on addition of benzene). Ilie yield is in the range 26-32 g (45-55%), m.p. 214-215°C. Similarly prepared are 4-methyl-2,5-bis-(m-nitrophenyI)-(39%), 4-methyl-2,5-bis-(m-bromophenyl)- (40%), and 4-methyl-2,5-bis-(p-nitrophenyl)imidazolcs (64%). 

Other compounds that have been similarly synthesized are 2,4-bis(4-methoxyphenyl)furan, 2,4-bis(4-biphenylyl)furan, 2,4-bis(4-bromophenyl)furan, 2,4-bis(4-chlorophenyl)furan, and 2,4-bis(4-nitrophenyl)furan. When MeOH (a proton donor) is added to the system containing phenacyl bromide [232], the principal products are acetophenone (53%) and 2-bromo-l,3-diphenyl-3,4-epoxy-butan-l-one (37%). If, to DMF containing lithium perchlorate and ethyl bromoacetate, phenacyl bromide is slowly introduced and reduced at mercury, the distribution of products is different [233] ... 

Preparative electrolyses of diphenyl disulfide and 4-bromophenyl 4-nitrophenyl disulfide afforded, respectively, sodium benzenesulfonate (20%) and bis(4-bromophenyl) and bis(4-nitrophenyl) disulfides with an overall yield of 80% [37]. 

Dichlorophenyl, 974 2-Bromophenyl, 974 4-Nitrophenyl, 974 4-Chloro-2-nitrophenyl, 975 2-Chloro-4-tritylphenyl, 975 2-Methoxy-5-nitrophenyl, 975 1,2-Phenylene, 975 4-Tritylaminophenyl, 976... 

The choice between Weygand s Schemes A and B proved difficult, with authors at one time favoring one Scheme and then the other. An early attempt to test the validity of the respective Schemes was made by Ruggli and Zeller, using diphenylacetoin (p-bromophenyl)hydrazone and di-phenylacetoin (p-nitrophenyl)hydrazone, which they treated with phenylhydrazine they obtained the bis(phenylhydrazone) in both cases. This result was taken by them to exclude Scheme B, which, under similar conditions, should yield a mixed osazone, but this conclusion is now invalidated by our knowledge of transhydrazonation, that is, the exchange of hydrazone residues, as in (20) (21), a possibility, which has caused... 

Furthermore, the electron-attracting triazole ring was found to facilitate the removal of bromine (but not of chlorine) during nitration thus, D-arobmo-hexose ( n-glucose ) (p-bromophenyl)osotriazole tetraacetate, when nitrated, gives D-arabino-hexose (p-nitrophenyl)osotriazole tetraacetate. ... 

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