Although the reaction conditions were not optimized, less substituted 1, 2, 4-triazines used in this work seem to give better yields when less than equimolar amounts of sodium borohydride are used, suggesting overreduction with an excess of the reagent. Some of the isolated 2, 5-dihydro-1, 2, 4-triazines of lower molecular weight are unstable since they gradually became colored on standing at room temperature, in contrast to the stable 5, 6- ...
