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.
[Ru(COD)Cl2]n (300 mg, 1 mmol), IMesH2Cl (1.47 g, 4 mmol), tricyclohexylphosphine (300 mg, 1 mmol), and KN(SiMe3)2 (540 mg, 2.5 mmol) were weighed directly into a 600 mL Schlenk tube. The flask was evacuated and filled with dry argon (2¡Á). Degassed benzene (300 mL) was added and the flask was pressurized to 30 psi with H2. The suspension was vigorously stirred for 12 hours at 90 C., yielding a bright yellow solution and white precipitate (1). After cooling the reaction to 5 C., propargyl chloride (0.3 mL, 4 mmol) was slowly added via syringe and the reaction mixture was allowed to warm to room temperature. The resulting brown benzene solution was washed with degassed 1M HCl (2¡Á), degassed brine (2¡Á), filtered through Celite and concentrated in vacuo to afford compound (2) as a brown solid in 90% yield (95% purity). The brown solid displayed catalytic behavior identical with previously synthesized second-generation catalysts. Analytically pure (2) was obtained by column chromatography on silica gel (degassed 3:1 hexanes/Et2O). 1H NMR (CD2Cl2): delta 18.49 (d, J=11.1 Hz, 1H), 7.26 (d, J=10.9 Hz, 1H), 6.97 (s, 2H), 6.77 (s, 2H), 3.92 (m, 4H), 2.58 (s, 6H), 2.37 (s, 6H), 2.29 (s, 3H), 2.23 (s, 3H), 0.88-1.584 (m, 33H), 1.06 (s, 3H), 1.08 (s, 3H). 31P NMR (CD2Cl2): delta 28.9. The reaction was repeated several times with one or more reaction conditions modified so as to optimize the yield of the product. It was found that the yield could be increased to greater than 95% by reducing the reaction temperature from 90 C. to 80 C., 173035-10-4
The synthetic route of 173035-10-4 has been constantly updated, and we look forward to future research findings.
Reference£º
Patent; CALIFORNIA INSTITUTE OF TECHNOLOGY; Grubbs, Robert H.; Chatterjee, Arnab K.; Choi, Tae-Lim; Goldberg, Steven D.; Love, Jennifer A.; Morgan, John P.; Sanders, Daniel P.; Scholl, Matthias; Toste, F. Dean; Trnka, Tina M.; (27 pag.)US9403854; (2016); B2;,
Chiral Catalysts
Chiral catalysts – SlideShare