Azo dyes derived from 2-methylbenzimidazole was written by Le Bris, M. Th.;Wahl, H.. And the article was included in Rev. textile-tiba in 1958.SDS of cas: 3012-80-4 This article mentions the following:
Methylation of 2-methyl-5(6)-nitrobenzimidazole gives a mixture containing 53% 1,2-dimethyl-6-nitrobenzimidazole (I), m. 250°, and 47% 1,2-dimethyl-5-nitrobenzimidazole (II), m. 227°. In neutral medium, 58% I is formed. I and II are separated by crystallization from alc. and form a eutectic, m. 198°, at 42% II. Nitration of 1,2-dimethylbenzimidazole gives a mixture of 63% I and 37% II. Methylation of I or II with Me2SO4 gives the 1,2,3-trimethyl-5(6)-nitrobenzimidazolium salt (III), m. 198°, very soluble in H2O; carbinol, m. 176°. Coupling of III with p-O2NC6H4N2Cl in aqueous pyridine or with p-O2NC6H4NHNO in buffered medium gives a dark green powder, which is not 4-O2NC6H4.N:C(CH2N2C6H4NO2-p).NMe (IV), as assumed by Poraǐ-Koshits and Muravich (C.A. 48, 11399e), but a diazo dye 3(4)-O2NC6H4.NMe.C[:C(N2C6H4NO2-p)2].NMe. To prepare IV, I or II is oxidized with SeO2 in PhMe at 95°, the PhMe removed by steam distillation, and the crude aldehyde (V) treated with p-O2NC6H4NHNH2 to yield yellow needles of IV (from aqueous pyridine). V and PhNHNH2 give orange red needles of the phenylhydrazone. III and ONC6H4NMe2 in the presence of piperidine give the corresponding azomethine, dark green tablets (from alc.); hydrolysis with dilute HCl and reaction with PhNHNH2 gives phenylazo-2-methylene-5(6)-nitro-1,3-dimethylbenzimidazoline, violet black rodlets (from aqueous pyridine); hydrochloride, orange red needles (from dilute HCl). Similarly prepared is p-nitrophenylazo-2-methylene-5(6)-nitro-1,3-benzimidazoline, dark red; hydrochloride, needles (from aqueous HCl or AcOH-HCl). In the experiment, the researchers used many compounds, for example, 1-Methyl-1H-benzo[d]imidazole-2-carbaldehyde (cas: 3012-80-4SDS of cas: 3012-80-4).
1-Methyl-1H-benzo[d]imidazole-2-carbaldehyde (cas: 3012-80-4) belongs to imidazole derivatives. Imidazole is the basic core of some natural products such as histidine, purine, histamine and DNA based structures, etc. Among the different heterocyclic compounds, imidazole is better known due to its broad range of chemical and biological properties. Imidazole is incorporated into many important biological compounds. The most pervasive is the amino acid histidine, which has an imidazole side-chain. Histidine is present in many proteins and enzymes, e.g. by binding metal cofactors, as seen in hemoglobin.SDS of cas: 3012-80-4
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem