Synthetic Route of 109838-85-9, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.
2,5-Dihydro-3,6-dimethoxy-2-isopropyl-5-(2′-iodo-4\5′-dibenzyloxybenzyl)- (2R,5S)-pyrazine (32); The diastereomeric product 32 was obtained by a reaction of the lithium salt of the chiral auxiliary (2R)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine with the bromo derivative 30 using a modification of a procedure reported in the literature [U. Schollkopf, “Enantioselective Synthesis of Non-Proteinogenic Amino Acids via Metallated Bis-Lactim Ethers of 2,5-Diketopiperazines.” Tetrahedron. 39, pp 2085-2091 (1983)]. Specifically, (2R)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine (15.7 mmol) was dissolved in 10 mL of THF (freshly distilled from LiAlH4). The light yellow solution was cooled to -78° C (dry ice/acetone bath) and stirred for 15 min under argon. A 2.5 M solution of n-butyl lithium (15.7 mmol) was added drop wise over a period of 10 min and the mixture was stirred for 20 min at -78° C. In a separate flask CuCN (7.86 mmol) was stirred with 10 mL of freshly distilled THF at room temperature for 10 min. The white suspension was then cooled to 0° C (ice bath) and stirred at that temperature for 20 min. The n-BuLi reaction mixture was then transferred to the white suspension of CuCN/THF under argon using a cannula. The resulting yellow suspension turned into a yellow solution within two minutes. The reaction mixture was then stirred at 0° C for 15 min and cooled to -78° C. After 15 min of stirring at -78° C, a solution of bromo derivative 30 (7.86 mmol) in 20 mL of freshly distilled THF was added drop wise. The color of the reaction mixture changed to greenish brown. After stirring for a further period of 2 h at – 78° C, the reaction mixture was warmed gradually to room temperature. The reaction mixture was then poured into a saturated solution of NH4Cl and extracted with EtOAc. The organic phase was dried over anhydrous Na2SO4, filtered and evaporated to afford an oily compound which was purified by silica gel flash column chromatography eluting with 5 percent ethyl acetate in hexane to yield pure 2,5-dihydro-3,6-dimethoxy-2-isopropyl-5- (2′-iodo-4′,5′-dibenzyloxybenzyl)-(2R,5S)-pyrazine (32) as a white solid in 70percent yield.
The synthetic route of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine has been constantly updated, and we look forward to future research findings.
Reference:
Patent; THE REGENTS OF THE UNIVERSITY OF CALIFORNIA; SATYAMURTHY, Nagichettiar; BARRIO, Jorge, R.; WO2010/117435; (2010); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem