24760-05-2

Upstream product

• 76-83-5 trityl chloride 
• 3471-32-7 4-Methoxyphenylhydrazine 
• 21650-57-7 (E)-1-(4-methoxyphenyl)-2-(4-methylphenyl)diazene 
• 71-43-2 benzene 
• 555-16-8 4-nitrobenzaldehdye 
• 603-38-3 4-(diphenylmethyl)aniline 
• 2945-12-2 1-(diphenylmethyl)-4-nitrobenzene 
• 93795-06-3 4-(4-Hydroxyphenylazo)triphenylmethan 
• 77-78-1 dimethyl sulfate 

Downstream Products

• 613-37-6 4-methoxylbiphenyl 
• 24760-11-0 Triphenylmethyl-p-methoxyphenyl-sulfon 
• 596-30-5 ditrityl peroxide 
• 100-66-3 methoxybenzene 
• 128527-01-5 (E)-1-(4-methoxyphenyl)-2-(4-(diphenylhydroxymethyl)phenyl)diazene 

Relevant academic research and scientific papers

Oxidation of 1-(4′-substituted phenyl)-2-(4-methylphenyl)diazene - Benzylic substitution vs. C-azo bond breaking

The low oxidation potential of 1-phenyl-2-(4-methylphenyl)diazene 4′-substituted with a dimethylamino or methoxy group (10 and 11) allows the easy single electron transfer with radical cation generation in the presence of FeCl3. At the same time, the stabilizing effect of the positive charge exerted by 4-dimethylaminophenyl > 4-methoxy groups on the intermediate carbocation favors the hydrogen atom elimination in comparison with proton loss. Whereas benzylic substitution towards di- and triarylmethane derivatives takes place starting from diazene 11, the oxidation of diazene 10 leads mainly to products of C-azo breaking. This difference is well-supported by the idea that the electron, in the first step of oxidation, is extracted from the azo and (or) from the amino nitrogen atom.

Phenylazo-Substituted Triphenylmethylium Systems

Triphenylmethanols (or their ethers) bearing phenylazo groups react with trifluoroacetic acid to give deeply colored solutions of the tritylium ions 7(+) - 9(+), (RC6H4N=NC6H4)nC(+)(C6H5)3-n (R = H, Me, Cl, NO2, MeO, H2N, Me2N), whose long wavelengths VIS absorptions and lowfield 1H-NMR signals are consistent with the existence of through-conjugated ?-electron systems.After addition of trifluoromethanesulfonic acid significant hypsochromic shifts of the VIS bands as well as additional proton deshieldings in the 1H-NMR spectrum are observed, which are in accordance with the formation of proximally azo-protonated phenylazotritylium ions 7(+)*H(+), 8(+)*2H(+), and 9(+)*3H(+), (RC6H4N=N(+)H-C6H4)nC(+)(C6H5)3-n.Fully analogous acid-strength-dependent ionisation/protonation reactions result for the overall p-substituted ions 17(+), 18(+), (RC6H4N=NC6H4)C(+)(C6H4R')2 (R,R' = Me, MeO, Me2N), as well as for the azobistritylium system 10(2+), (C6H5)2C(+)C6H4N=NC6H4C(+)(C6H5)2, and its azoxy derivative 11(2+).The linearly extended bis- and trisazo systems 19(+), 22(+), MeC6H4N=N(C6H4N=N)1,2C6H4C(+)(C6H5)2 and the (phenylazo)styryl system 20(+), MeC6H4N=NC6H4CH=CHC6H4C(+)(C6H5)2 in trifluoroacetic acid do not show any significant color changes relativ to the corresponding monofunctional parent types.In trifluoromethanesulfonic acid, however, compounds 19(+), 22(+) exhibit the usual bathochromic shifts of the longest wavelenght VIS absorption accompanying the increasing protonation of the polyazo system.In the case of the tritylium ions containing azomethine bridges, 24(+), only for the methoxy derivative 24b(+) indications for the existence of the conjugatively extended tritylium system (MeOC6H4N=CHC6H4)C(+)(C6H5)2 are found.The amide derivatives 26(+)-29(+), on the other hand, presents no clues for the existence of through-conjugated systems of the kind ArC(OH)=NC6H4C(+)Ar2 and ArN=C(OH)C6H4C(+)Ar2, respectively.