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o-Tolidine Alkylation
Published in John R. Kosak, Thomas A. Johnson, Catalysis of Organic Reactions, 2020
Kevin R. Lassila, Michael E. Ford, Susan M. Clift, Jeremiah P. Casey, Paula L. McDaniel
The present study was initiated in order to examine application of heterogeneous acid catalyzed arylamine alkylation to the production of alkylated derivatives of o-tolidine. The rigid geometry and high symmetry of o-tolidine would be of particular interest in the lucrative high performance polymer market. However, the high melting point and rather high amine reactivity, as well as concerns about chronic toxicity, promised to offset any potential property enhancements in the derived polymers. Alkylation would decrease the symmetry of the molecule, diminishing the melting point and enhancing processibility while producing a sterically encumbered amine with attenuated reactivity. Based on the decreasing chronic toxicity observed in the series benzidine, tolidine, and tetramethylbenzidine, alkylated derivatives of tolidine would be expected to exhibit reduced chronic toxicity [3]. Alkylation would not affect the rigidity of the skeleton and was not expected to significantly detract from the performance of the product.
Thin-Layer Chromatography in Clinical Chemistry
Published in Bernard Fried, Joseph Sherma, Practical Thin-Layer Chromatography, 2017
Gardyan and co-workers12 conducted systematic investigations concerned with separation and detection of about 150 pesticides (mainly insecticides and fungicides). Most of pesticides mixtures were separated in NP systems with silica gel, the remaing ones in C18 RP systems. Silver nitrate-UV irradiation, chlorine-o-tolidine, and cholinesterase inhibition were used for visualization. It was indicated that the enzymatic reaction is realized only on a TLC plate with silica gel, and that computer-assisted densitometric evaluation allows direct quantitative determination of pesticides.
Analytical Chemistry
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Tannic acid (reagent for albumin, alkaloids, and gelatin). Dissolve 10 g of tannic acid in 10 mL of ethanol and dilute with distilled water to 100 mL. Titration mixture (residual chlorine in water analysis). Prepare 1 L of dilute HCl (100 mL of HCl (sp. gr. 1.19) in sufficient distilled water to make 1 L). Dissolve 1 g of o-tolidine (3,3'-dimethylbenzidine , CAS No. 119-93-7) in 100 mL dilute hydrochloride, stir well and dilute to 1 L using dilute HCl solution. Tollen's Reagent (confirming the presence of aldehydes). 5 drops of 5% NaOH is added to 2 mL 10% aqueous silver nitrate in a test tube. The insoluble silver (I) oxide dissolved by the drop wise addition of 10% aqueous ammonia (ammonium hydroxide) yields a clear solution. Excess ammonium hydroxide should be avoided as it may give false positive result. Approximately 10 drops of the aldehyde will yield a silver mirror coating on the test tube inner wall, especially if the mixture is warmed up to 50 oC. Trinitrophenol solution. See Picric acid. Turmeric tincture (reagent for borates). Digest ground turmeric root with several quantities of distilled water which are discarded. Dry the residue and digest it several days with six times its weight of ethanol. Filter. Uffelmann's reagent (turns yellow in presence of lactic acid). To a 2% solution of pure phenol in distilled water, add an aqueous solution of iron (III) chloride until the phenol solution becomes violet in color. Wagner's reagent. See Iodo-potassium iodide. Wagner's solution (used in phosphate rock analysis to prevent precipitation of iron and aluminum). Dissolve 25 g of citric acid and 1 g of salicylic acid in distilled water and dilute to 1 L. Use 50 mL of the reagent. Wij's iodine monochloride solution (for iodine number). Dissolve 13 g of resublimed iodine in 1 L of glacial acetic
Adsorptive removal of aromatic amine from aqueous solutions using carbon black as adsorbent
Published in Chemical Engineering Communications, 2023
Layza Rodrigues, Lucas Destefani Paquini, Ueslei Giori Favero, Ruan de Oliveira Alves, Iara Rebouças Pinheiro, Renato Ribeiro Passos, Luciano de Moura Guimarães, Luciene Paula Roberto Profeti, Demetrius Profeti
Ortho-tolidine (o-tolidine; 3,3-dimethylbenzidine) is an aromatic amine (Figure 1) widely used as a reagent in azo dyes synthesis, such as Direct Red 2 and Direct Blue 15 (Cerniglia et al. 1982). O-tolidine is also commonly employed by basic sanitation sectors that routinely determine the residual chlorine level within treated the drinking water. In this analysis, the aromatic amine is rapidly oxidized into iminoquinone in the presence of Cl2 at pH < 2.8 and the reaction product changes the medium color to yellow, with intensity directly proportional to the Cl2 concentration present in the solution (Salami et al. 2009).