Guanidine → 2-(4-Ethyl-7-methyl-benzo[b]thiophen-5-yloxy)-3-phenylamino-acrylonitrile

Participants

Reaction Steps

3,3-Bis-dimethylamino-2-(4-ethyl-7-methyl-benzo[b]thiophen-5-yloxy)-propionitrile (590 mg, 2 mmol) and aniline HCl (1.1 g, 9 mmol) in 5 mL absolute ethanol were heated at reflux for 2.0 hours. In a separate flask, guanidine HCl (0.850 mg., 9 mmol) and sodium methoxide solution (1.83 ml, 9 mmol, 4.9 molar solution in methanol) were mixed in 1 ml Ethanol. The guanidine solution was added to the reaction mixture via pipette, and the reaction mixture was heated to reflux for 5 hours, then cooled. Solvent was removed in vacuo, and the residue was, chromatographed (5% MeOH/methylene chloride/1% NH4OH) to give 368 mg 2-(4-Ethyl-7-methyl-benzo[b]thiophen-5-yloxy)-3-phenylamino-acrylonitrile, 61%. Also present was 50 mg of 5-(4-Ethyl-7-methyl-benzo[b]thiophen-5-yloxy)-pyrimidine-2,4-diamine, 9%.

Provenance & Evidence