Yield:1378802-34-6 91.1%

Reaction Conditions:

with copper(l) iodide;tetrakis(triphenylphosphine) palladium⁽⁰⁾;triethylamine in acetonitrile at 20; for 15 h;Inert atmosphere;Reagent/catalyst;

Steps:

1.1; 2.1; 3.1 Synthesis of compound (2) 2-methyl-4-(3-chloropyrazine)-3-butyn-2-ol

Add 2,3-dichloropyrazine (100g, 0.676mol, 1eq), cuprous iodide (12.8g, 0.067mol, 0.1eq), Pd(PPh3)4 (15.6g, 0.0135mol, 0.02 eq), 1L triethylamine and 1L acetonitrile, protected by nitrogen, add 2-methyl-3-butyn-2-ol (62g, 0.737mol, 1.1eq) dropwise at room temperature, after the addition, stir at room temperature for 15h, after the reaction is complete, the reaction solution is directly concentrated, and column chromatography is used to obtain 120 g of compound (2) 2-methyl-4-(3-chloropyrazine)-3-butyn-2-ol with a yield of 91.1% .

References:

CN111606920,2020,A Location in patent:Paragraph 0047-0050; 0060-0062; 0069-0071