Reference of 767340-03-4, The chemical industry reduces the impact on the environment during synthesis 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, I believe this compound will play a more active role in future production and life.
Into a 500 ml flask were charged chloro(1,5-cyclooctadiene)rhodium(I) dimer {[Rh(cod)Cl]2}(292 mg, 1.18 mmol) and (R,S) t-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 24 (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 C. for 13 h. Assay yield was determined by HPLC 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 H3PO4 solution (0.5 M, 95 mL). After separation of the layers, 3N NaOH (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 C). The hot toluene solution was then allowed to cool to 0 C. slowly (5-10 h). The crystals were isolated by filtration (13 g, yield 72%, 98-99% ee); m.p. 114.1-115.7 C. 1H NMR (300 MHz, CD3CN): delta7.26 (m), 7.08 (m), 4.90 (s), 4.89 (s), 4.14 (m), 3.95 (m), 3.40 (m), 2.68 (m), 2.49 (m), 1.40 (bs). Compound 2-5 exists as amide bond rotamers. Unless indicated, the major and minor rotamers are grouped together since the carbon-13 signals are not well resolved: 13C NMR (CD3CN): delta171.8, 157.4 (ddd, JCF=242.4,9.2,2.5 Hz), 152.2 (major), 151.8 (minor), 149.3 (ddd; JCF=246.7, 14.2, 12.9 Hz), 147.4 (ddd, JCF=241.2, 12.3, 3.7 Hz), 144.2 (q, JCF=38.8 Hz), 124.6 (ddd, JCF=18.5, 5.9, 4.0 Hz), 120.4(dd, JCF=19.1, 6.2 Hz), 119.8 (q,JCF=268.9 Hz), 106.2 (dd, JCF=29.5, 20.9 Hz), 50.1, 44.8, 44.3 (minor), 43.2 (minor), 42.4, 41.6 (minor), 41.4, 39.6, 38.5 (minor), 36.9.
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, (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, other downstream synthetic routes, hurry up and to see.
Reference:
Patent; Thornberry, Nancy A.; Kaufman, Keith D.; US2006/270722; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem