Acetic Acid → HCID 70267818, compound

Participants

Reaction Conditions

Reaction Steps

70.0 g of 2-keto-4-(2,3-dimethoxyphenyl)-3-butenoic acid (0,30 moles) dissolved in 700 ml of ethanol are placed into a hydrogenator, then 43.0 g of an 8.03M (0.34 mole) methylamine solution and glacial acetic acid under nitrogen atmosphere are added to pH from 8 to 9, keeping the temperature below 25° C. Stirring is continued for about 15 minutes, then 14.0 g of 5% Pd/C (about 50% humidity) are added, under hydrogen pressure (40 psi, room temperature) for 6 hours. The reaction mixture is then adjusted to markedly acid pH with concentrated HCl, filtered and the solution is evaporated to dryness. The resulting solid is taken up and triturated with heating (50° C.) with 300 ml of acetone, then it is left to cool under stirring, filtered and dried under vacuum at 40° C. Yield: 51 g, 60% (moles), 73%(weight); TLC: methylene chloride/methanol/acetic acid 75/20/10; Rf=0,5; Developer: ninhydrin. M.p.=165°-166° C.

Provenance & Evidence