Synthesis of Yellow 1 Methacrylate

To a cold solution (0 °C) of (E)−4-phenyl azophenol (5 g, 0.025 mol) in dichloromethane (200 mL) triethylamine (5.78 g, 0.057 mol) was added. The reaction vessel was connected to a sodium hydroxide bubbler and sealed. To the solution, methacryloyl chloride (3.711 g, 0.355 mol) was added dropwise, and left stirring at 500 rpm for 4 h. The solution was quenched with saturated sodium carbonate solution (79 mL). The aqueous layers were extracted with dichloromethane, and the combined organic layers were washed with brine, and the solvent was evaporated. The resulting yellow-brown powder was dissolved in petroleum ether. The solution was purified through a silica gel column with petroleum ether as eluent, and the solvent was then evaporated. The product was then columned through basic alumina with petroleum ether, to yield a yellow powder of yellow 1 methacrylate. ¹H NMR (400 MHz, CDCl₃): δ 2.11 (3H, s, C = CCH₃), 5.82 (1H, m, C = CHH), 6.42 (1H, s, C = CHH), 7.32 (2H, m, 2× ArH), 7.47–7.58 (3H, m, 3× ArH), 7.94 (2H, m, 2× ArH), 8.00 (2H, m, 2× ArH) ppm.