Dimethylformamide dimethyl acetal → 1-(2-Methylphenyl)-4-methylamino-1,2-dihydro-1,3,5-triazin-2-one

Participants

Reaction Steps

To a magnetically stirred suspension of 9.72 g (40 mmol) of 1-(2-methylphenyl)-3-methylamidinourea hydrochloride in 30 ml of CH3CN was added 9.52 g (80 ml) of N,N-dimethylformamide dimethylacetal. After the mixture had been further diluted with 25 ml CH3CN and stirred for 5 minutes, all of the solid had dissolved. TLC(3% NH4OH/IPA showed a new spot; about equal in size to a spot in starting material; (EtOAc/MeOH; 9:1) shows mostly a new spot. The solution was refluxed for two hours. The reaction mixture was allowed to cool to ambient temperature. The reaction mixture was then poured into CHCl3 /H2O and separated. The aqueous layer was extracted with CHCl3 (for a total of 3×50 ml). The organic layers were combined and washed with H2O (2×50 ml). The aqueous layers were combined and back-extracted with CHCl3 (1×50 ml). All organic layers were combined, dried, filtered and concentrated in vacuo to yield the product which was recrystallized from absolute EtOH, filtered and washed with cold absolute EtOH and air-dried. The product was 1-(2-methylphenyl)-4-methylaminodihydro-1,3,5-triazin-2-one, melting point 191.5°-192.5° C.

Provenance & Evidence