L-bromo-2-nitrobenzenes

O2N.CBH4.NH.C6H4.NO2 golden-yel Ifts, mp 166—69°. It can be prep from 2-nitroaniIine and 2-bromo-l-nitrobenzene on heating in Na carbonate soln with CugClg catalyst at 180° Refs 1) Beil 12, 690 (341) 2) P. Juillard,... 

Nitro-N, N-dipropylaniline, It-green crysts, mp 59°. It was prepd by heating 4-bromo-l nitrobenzene with dipropylamine in a tube at 183°(Refs 2 3)... 

Dinitrobenzene is unreactive under these conditions. Replacement with fluorine appears to take place only when a halogen atom is present in the ortho- or meta-position relative to the nitro group. 4-Bromo-l,2-dinitrobenzene (3) has been converted to 4-bromo-2-fluoro-l-nitrobenzene (4) by heating with potassium fluoride in dimethylformamide at 100 C for 2 hours.138... 

Bromo-l-[Pg.1893]

The chemistry of indium metal is the subject of current investigation, especially since the reactions induced by it can be performed in aqueous solution.15 The selective reductions of ethyl 4-nitrobenzoate (entry 1), 2-nitrobenzyl alcohol (entry 2), l-bromo-4-nitrobenzene (entry 3), 4-nitrocinnamyl alcohol (entry 4), 4-nitrobenzonitrile (entry 5), 4-nitrobenzamide (entry 6), 4-nitroanisole (entry 7), and 2-nitrofluorenone (entry 8) with indium metal in the presence of ammonium chloride using aqueous ethanol were performed and the corresponding amines were produced in good yield. These results indicate a useful selectivity in the reduction procedure. For example, ester, nitrile, bromo, amide, benzylic ketone, benzylic alcohol, aromatic ether, and unsaturated bonds remained unaffected during this transformation. Many of the previous methods produce a mixture of compounds. Other metals like zinc, tin, and iron usually require acid-catalysts for the activation process, with resultant problems of waste disposal. 

Gas chromatographic examination of another reaction mixture run on a 10-mmol scale with undecane as an internal standard indicates that 2-methyl-4 -nitrobipheny1 is formed in 90% yield based on l-bromo-4-nitrobenzene. The product obtained by this procedure shows the following properties mp 99-101 C (lit., mp 103-105°C) IR (neat) cm l 1600 (s), 1510 (s), 1480 (s), 1340 (s),... 

Identify the product from each of the following reactions (a) l-chloro-4-nitrobenzene + sodium methoxide (b) l,2-dichloro-4-nitrobenzene + 1 mole of sodium methoxide (c) 4-(2-chlorophenyl)-butanonitriie + sodium amide (d) 3-bromo-4 methylbiphenyl + potassium amide,... 

Suggest routes to the following compounds starting from benzene (a) l-chloro-4-nilrobenzene (b) l-bromo-3-nitrobenzene (c) 4-methoxybenzonitrile (d) fluorobenzene. 

Tom and coworkers published three new types of phosphines derived from diarylsul-fones, tritylimidazole or 2-bromobenzophenone (Figure 13). Their activity in palladium-catalyzed amination of aryl bromides is not general, but they do catalyze the coupling of certain substrates. For example, the coupling of morpholine with l-bromo-4-nitrobenzene (97% with 47), 4-bromo-f-butylbenzene (81% with 48) and 4-bromoanisole (96% with 49) was achieved in high yields160. 

The synthetic potential of these catalysts has been investigated in Heck-type coupling reactions treatment of l-bromo-4-nitrobenzene with n-butyl acrylate in isopropyl alcohol in the presence of 2.5 mol% of catalyst and tetrabutylammonium acetate afforded the unsaturated ester in an excellent... 

How would you prepare the following compounds from the named starting material (a) l-methoxy-3-nitrobenzene from ben-zenesulfonic acid (b) methyl 2-hydroxybenzoate from phenol (c) 2-bromo-4-methylphenol from toluene. 

C6H4BrN02 l-Bromo-3-nitrobenzene 328.2 20.2 0.81413E+02 -0.27645E+00 0.27367E-03 328-413... 

BusP as ligand.Poor yields in the reductive cyclization method—when competitive cyclization is possible—and also the need for milder reaction conditions in the cyclization step urged Emoto et al. to report an alternative method based on sequential palladium-catalyzed aryl amination (Scheme 10). The substrate for the cyclization was 2-amino-2 -bromo-diphenylamine, obtained by selective bromination and reduction of the well-known 2-nitrodiphenyl-amines or by coupling of 2-bromoaniline with a l-bromo-2-nitrobenzene and subsequent reduction. Treatment of 2-bromo-2 -nitrodiphenylamine with catalytic amounts of palladium(II) and BINAP as ligand afforded the desired phenazines in good yields. ... 

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