92114-99-3

Upstream product

• 121-72-2 N,N-dimethyl-m-toluidine 
• 100-05-0 4-nitrobenzenediazonium chloride 
• 100-01-6 4-nitro-aniline 

Downstream Products

• 92115-09-8 Dimethyl-[3-methyl-4-(4-nitro-phenylazo)-phenyl]-amine 

Relevant academic research and scientific papers

A novel indicator series for measuring pKa values in acetonitrile

A series of substituted azobenzene dyes was found to span a range of 8 pKa units in acetonitrile. The UV absorption spectra of the dyes are responsive to protonation, changing in both absorption maximum and intensity. These characteristics make the dyes useful as indicators for the measurement of pKa values of neutral organic bases that absorb in the visible region of the spectrum.

THERMAL ISOMERIZATION OF AZOBENZENES. III. SUBSTITUENT, SOLVENT, AND PRESSURE EFFECTS ON THE THERMAL ISOMERIZATION OF PUSH-PULL AZOBENZENES.

The substituent, solvent, and pressure effects on the rate of the thermal cis-to-trans isomerization of 4-dimethylamino-4 prime -nitroazobenzene (NDAAB) derivatives have been studied. 2-Methyl- and 2 prime -chloro-NDAAB isomerize faster than NDAAB, and 2 prime -methyl- and 2-chloro-NDAAB isomerize slower than NDAAB. For 2,2 prime -dimethyl- and 2,2 prime -dichloro-NDAAB, the rates are between those of the monosubstituted ones. These findings are very similar to those for 4-(dimethylamino)azobenzene (DAAB) derivatives, and no fundamental difference in the kinetic-substituent effects was observed between NDAAB and DAAB. The volume of activation, which is of a negative value, varies remarkably from solvent to solvent and from substituent to substituent; its magnitude increases generally with an increase in the solvent polarity.

Steric Effects in 4-Dimethylaminoazobenzenes and Their Protonated Species

The effects of steric crowding in the amino-substituted ring of the 4-dimethylaminoazobenzene system have been examined by electronic absorption spectroscopy, using methyl substituents to induce loss of planarity.The most significant effects are produced by methyl groups ortho to the amino group.No evidence for electronic buttressing could be found in the case of dyes with electron withdrawing groups in the second benzene ring.The effects of steric crowding in the protonated forms of the dyes have also been examined.