Application of 78342-42-4,Some common heterocyclic compound, 78342-42-4, name is (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine, molecular formula is C9H16N2O2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
To a solution of 3.32 g (18 mmol) of commercially available (2S)-2, 5-dihydro- 3,6-dimethoxy-2-isopropylpyrazine in 100 mL OF TETRAHYDROFURAN AT-70 °C was added 12 mL (19 mmol) of a 1.6M solution of butyllithium in hexanes. After stirring at this temperature for 20 min, 5 g (19.5 mmol) of 2-fluoro-4-trifluoromethylbenzyl bromide in 20 ML of tetrahydrofuran was added and stirring was continued for 3 h before warming the reaction to ambient temperature. The reaction was quenched with water, concentrated in vacuo, and extracted with ethyl acetate. The combined organic phase was washed with brine, dried, and concentrated in vacuo. Purification by flash chromatography (silica gel, 0-5percent ethyl acetate in hexanes) afforded the title compound. 1H NMR (500 MHz, CDC13) : 6 7.33-7. 25 (m, 3H), 4.35-4. 31 (m, 1H), 3.75 (s, 3H), 3.65 (s, 3H), 3.60 (t, 1H, J = 3.4 Hz), 3.33 (dd, 1H, J = 4.6, 13.5 Hz), 3.03 (dd, 1H, J = 7,13. 5 HZ), 2.25-2. 15 (m, 1H), 1.0 (d, 3H, J = 7 HZ), 0.66 (d, 3H, J = 7 HZ).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine, its application will become more common.
Reference:
Patent; MERCK & CO., INC.; WO2004/58266; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem