With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.173035-10-4,1,3-Dimesityl-4,5-dihydro-1H-imidazol-3-ium chloride,as a common compound, the synthetic route is as follows.
A mixtureof 2,4,6-trimethylaniline (11.9 g, 0.088 mol), triethyl orthoformate (7.1 g, 0.048 mol)and acetic acid (0.12 mL) was heated at reflux (?120 ) for 5 h. The mixture wasevaporated until dry under reduced pressure. A mixture of dichloroethane (25 mL)and diisopropylethylamine (8.9 mL, 0.05 mol) was added to the precipitate and afterthat the suspension was stirred at 120 for 5 h in a hermetically sealed Schlenkflask. The formed solution was evaporated to dryness under reduced pressure. Theobtained precipitate was washed with acetone (85 mL) and dried under vacuum at rt.The residue was dissolved in chloroform (300 mL) at 0 C, and then granulatedNaOH (68.0 g, 1.70 mol, with a pellet diameter of ?0.5 mm) was added in one portionto the solution at the same temperature under vigorous stirring. Stirring wascontinued until the temperature reaches 18 C (?40 min), then the reaction wasstirred at this temperature for another 4 h (until the end of the heat release process).The precipitate (NaOH) was filtered off, washed with chloroform (2 ¡Á 40 mL) andhexane (2 ¡Á 40 mL). After the last operation, sodium hydroxide can be used onemore time in the same step. The filtrate was evaporated under reduced pressure.The solid residue was treated with hexane (70 mL) under ultrasonic irradiation for 10min and then held at 4 C for 24 h. The precipitate was filtered off, suspended withmethanol (60 mL), treated by ultrasonic irradiation for 2 min and filtered off. The lastoperation was repeated three more times, after that the white powder was driedunder vacuum at rt to give 14.3 g of the title compound 9 (87% relative to the starting2,4,6-trimethylaniline) with >95% purity (by 1H NMR)., 173035-10-4
173035-10-4 1,3-Dimesityl-4,5-dihydro-1H-imidazol-3-ium chloride 2734917, achiral-catalyst compound, is more and more widely used in various fields.
Reference£º
Article; Polyanskii, Kirill B.; Alekseeva, Kseniia A.; Raspertov, Pavel V.; Kumandin, Pavel A.; Nikitina, Eugeniya V.; Gurbanov, Atash V.; Zubkov, Fedor I.; Beilstein Journal of Organic Chemistry; vol. 15; (2019); p. 769 – 779;,
Chiral Catalysts
Chiral catalysts – SlideShare