Wi-Dinitrobenzene

Nitrations are usually carried out at comparatively low temperatures at higher temperatures there may be loss of material because of the oxidising action of the nitric acid. For substances which do not nitrate readily with a mixture of concentrated nitric and sulphuric acids ( mixed acid ), the intensity of the reaction may be increased inler alia by the use of fuming sulphuric acid (containing up to 60 per cent, of sulphur trioxide) or by fuming nitric acid. Thus nitrobenzene is converted by a mixture of fuming nitric acid and concentrated sulphuric acid into about 90 per cent, of wi-dinitrobenzene and small amounts of the o- and p-isomers the latter are eliminated in the process of recrystallisation ... 

Nitro compounds. Nitromethane Nitrobenzene wi-Dinitrobenzene. Amides and imides. Acetamide n-Caproamide Acetanilide Benz-anilide Phthalimide. 

A -Alkylcarbazoles formed yellow to orange to deep brown 1 1 charge transfer crystals with wi-dinitrobenzene, 3,5-dinitrobenzoic acid (3,5-DNBA) and its derivatives (Scheme 30) [57]. On the other hand, attempts to obtain adduct crystals of A -alkylcarbazoles with o- or p-dinltrobenzene and with 2,4- or 3,4-dinitrobenzoic acid failed. Upon solid-state photolysis, many of these adduct crystals underwent photoredox reactions and e a position of the A -alkylcarba-zoles was oxidized to produce carbazole, JV-acylcarbazoles, and A/-(hydroxy-... 

The dipole moment is a property of the molecule that results from charge separations like those discussed above. However, it is not possible to measure the dipole moment of an individual bond within a molecule we can measure only the total moment of the molecule, which is the vectorial sum of the individual bond moments.32 These individual moments are roughly the same from molecule to molecule,33 but this constancy is by no means universal. Thus, from the dipole moments of toluene and nitrobenzene (Figure 1.10)34 we should expect the moment of p-nitrotoluene to be about 4.36 D. The actual value 4.39 D is reasonable. However, the moment of p-cresol (1.57 D) is quite far from the predicted value of 1.11 D. In some cases, molecules may have substantial individual bond moments but no total moments at all because the individual moments are canceled out by the overall symmetry of the molecule. Some examples are CC14, tr[Pg.16]

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