Reaction of 3,5-dichloro-4H-1,2,6-thiadiazin-4-one with (R) and (S)-3-methylmorpholines (2 equiv), in THF, at ca. 20 °C gave (R) and (S)-3-chloro-5-(3-methylmorpholino)-4H-1,2,6-thiadiazin-4-ones in 95 and 97% yields, respectively. The new compounds were fully characterized.