2-methyl-6-[(methylamino)methyl]-3,4-dihydroquinazolin-4-one synthesis

Yield:1235852-48-8 69.4%

Reaction Conditions:

in water at -10 - 20;

Steps:

1.1; 2.1; 3.2 (1) Preparation of 6-((methylamino)methyl)-3,4-dihydro-2-methyl-4-oxo-6-quinazoline (Compound 1)

Add 6-bromomethyl-3,4-dihydro-2-methyl-4-oxo-6-quinazoline (m=77.50g, n=1mol) slowly to 40% methylamine aqueous solution (m=77.50g, n=1mol) =25.3g, n=0.1mol), the temperature is controlled at -10~-5, gradually warm up to room temperature after the addition is completed, continue to stir, and confirm that the reaction is complete (TLC detection).Add sodium bicarbonate solution to the reaction solution, adjust the pH to alkaline (pH>7), extract with dichloromethane, wash the organic phase with saturated sodium chloride aqueous solution, rotate the organic phase to remove the solvent, and then add 500 mL of water to make a slurry , Stirred for 30 minutes, filtered, the filter cake was washed with water (3×100 mL), sucked dry and dried to obtain an off-white solid (14.1 g, 69.4%).

References:

CN105111197,2021,B Location in patent:Paragraph 0053-0061; 0094-0098; 0115; 0120; 0121