Acetoin → 2-Amino-4,5-dimethyl-1-(2,4,6-trimethylphenyl)-1H-pyrrole-3-carbonitrile

Participants

Reaction Steps

A mixture of 3-hydroxy-2-butanone (100.000 g, 1.135 mol), 2,4,6-trimethylaniline (153.225 g, 1.135 mol) and p-toluenesulfonic acid (0.670 g) in 500 ml of benzene was refluxed using a Dean-Stark trap to remove water. After 2 hours, malononitrile (75.000 g, 1.135 mol) was added and the mixture was refluxed for an additional 10 hours until all of the starting material was consumed. The reaction mixture was cooled and precipitate formed and filtered. The solid was washed with a minimum amount of ethanol. The solid was diluted with 500 ml of benzene and product was dissolved. Some undesired product was insoluble and was filtered off. The filtrate was concentrated to give a tan solid which was recrystallized from ethanol to give 130.260 g of off-white crystals. 1H NMR (CDCl3) δ 1.68(s, 3H), 1.93(s, 6H), 2.05(s, 3H), 2.31(s, 3H), 3.62(brs, 2H), 6.95(s, 2H) ppm.

Provenance & Evidence