Regioselective alkylations of optically active 4,5-dihydro-1,2,4-triazin-6(1H)-ones

Regiocontrolled alkylations of chiral 4,5-dihydrotriazin-6-ones using sodium hydride in DMF are reported. By this approach different N1-alkyl, N1,N4-dialkyl and N4-alkyl dihydrotriazinones could be obtained in good yields with conservation of their optical activity.