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Electric Literature of 77168-85-5, These common heterocyclic compound, 77168-85-5, name is Methyl 5-chloro-6-methylpyrazine-2-carboxylate, its 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.

Water (500ml) and Compound ll-a (85.0 g) were changed into a flask and the mixture was agitated for 10 to 20 minutes. Potassium Phosphate (127g) and toluene (500ml) were charged into the reaction. The batch was agitated until all solids were dissolved. The aqueous was split and the organic phase was concentrated to about 170ml or less if possible under vacuum. 1-Methyl-2- pyrrolidinone (NMP) (204 ml) was charged to the batch, which was further concentrated to about 300 ml under vacuum. The batch was cooled to below O0C. To the batch, Compound ll-b (5Og) and N, N diisopropylethylamine (60ml) were charged. The batch was heated to 9O0C for about 17 hours unti. the reaction was completed. The batch was concentrated under vacuum at 8O0C until no distillate came out. The batch was cooled to 20 0C. Water (255 ml) and TBME (510 ml) were added into the batch. The mixture was agitated and phases were separated in a separation funnel. The organic layer was washed again with 250 ml of water. The combined aqueous layer was back extracted with 200 ml of TBfVIE. The combined organic iayer was washed with 0.5N HCi (100 ml). The batch was concentrated at vacuum unti. 255ml TBME (510 mi) was charged info the batch and concentrated to 250 mi. After cooling to Q- 1O0C, a solution of 2-isopropanol hydrochloride solution (5-6N1 170ml) was added under 250C and the solution was agitated at 15-25 0C for 20 hours. TBME (255 ml) was charged into the batch and agitated at 25 0C for 2 hours. The batch was filtrated and washed with a mixture of T8ME/2-Isopropanol. (200 ml, 2/1 v/v). The wet cake was dried at vacuum oven at 50 0C to give 65.0 g (77percent) of the white solid. 1H NMR(400 MHz in CD3OD): 8.86 (S5 1 H)1 4.83(S, 2H), 3.94(m, 4H); 3.53 (m, 3H); 3.24 (t, 1 H); 2.99 (dd, 1 H); 2.66 (S5 3H)1 1.82 (m, 2H); 1.11 (m, 6H). 13C NMR (400 Mhe, CD3OD): delta 165.3; 160.4; 152.4;143.3; 139.2′ 58.3; 53.8; 53.8; 51.5; 49.9, 25.1 ; 21.4; 17.1 , 10.6.

Statistics shows that Methyl 5-chloro-6-methylpyrazine-2-carboxylate is playing an increasingly important role. we look forward to future research findings about 77168-85-5.

Reference:
Patent; SCHERING CORPORATION; WO2009/79490; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem