4-Methyl-N-(4-methylphenyl)-N-phenylbenzenamine

Uses4,4'-Dimethyltriphenylamine (DMTPA) can be used as a starting material for the synthesis of 4-[bis(4-methylphenyl)amino]benzaldehyde (BMABA). BMABA is a molecule exhibiting mechanophluorescence, and it has applications in fields such as sensors, data storage and smart switches [5]. The reaction process and mechanism are as follows:This synthesis method is carried out via the Vilsmeier-Haack reaction. DMTPA (1.37 g, 5.01 mmol) was dissolved in DMF (2.3 mL, 29.8 mmol), and trichlorooxaphosphorane (0.46 mL, 5.02 mmol) was slowly added under an ice-water bath. Upon completion of the addition, the reaction temperature was adjusted to 100 °C and the mixture was heated for 3 h. After cooling to room temperature, the product was dissolved in dichloromethane, then neutralised with a sodium bicarbonate solution, extracted, dried over anhydrous Na₂SO₄, and the solid product was collected by vacuum distillation. Chromatographic separation was performed on a silica gel column using a mobile phase of dichloromethane and methanol (Vdichloromethane:Vmethanol = 100:1), yielding pale yellow BMABA (1.14 g, 75.6% yield).