A common compound: 767340-03-4, name is (2Z)-4-Oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazine-7(8H)-yl]-1-(2,4,5-trifluorophenyl)but-2-en-2-amine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below. 767340-03-4
Into a 500 ml flask were charged chloro(l,5-cyclooctadiene)rhodium(I) dimer{[Rh(cod)Cl]2}(292 mg, 1.18 mmol) and (R,S) f-butyl Josiphos (708 mg, 1.3 mmol) under a nitrogen atmosphere. Degassed MeOH was then added (200 mL) and the mixture was stirred at room temperature for 1 h. Into a 4 L hydrogenator was charged the enamine amide 2^4 (118 g, 0.29 mol) along with MeOH (1 L). The slurry was degassed. The catalyst solution was then transferred to the hydrogenator under nitrogen. After degassing three times, the enamine amide was hydrogenated under 200 psi hydrogen gas at 50 0C for 13 h. Assay yield was determined by EtaPLC to be 93% and optical purity to be 94% ee. The optical purity was further enhanced in the following manner. The methanol solution from the hydrogenation reaction (18 g in 180 mL MeOH) was concentrated and switched to methyl t- butyl ether (MTBE) (45 mL). Into this solution was added aqueous Eta3PO4 solution (0.5 M, 95 mL).After separation of the layers, 3NNaOH (35 mL) was added to the water layer, which was then extracted with MTBE (180 mL + 100 mL). The MTBE solution was concentrated and solvent switched to hot toluene (180 mL, about 75 0C). The hot toluene solution was then allowed to cool to 0 0C slowly (5 – 10 h). The crystals were isolated by filtration (13 g, yield 72%, 98 – 99% ee); m.p. 114.1 – 115.7 0C. EPO
In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 767340-03-4, other downstream synthetic routes, hurry up and to see.
Reference:
Patent; MERCK & CO., INC.; WO2006/119260; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem