反应详情

7.22 grams of a 50% aqueous sodium hydroxide solution are added to a stirred mixture of methyl guanidine sulfate (9.76 g) in 200 ml of THF. The mixture is stirred for one half hour followed by the addition of anhydrous Na2SO4 (10 g). The mixture is stirred for an additional one half hour. 8.0 grams of 2,6-dimethyl-4-methoxyphenyl isocyanate in 50 ml of THF are added dropwise to the reaction mixture and the mixture stirred overnight. The reaction mixture is filtered and concentrated in vacuo to obtain a yellow oil. The yellow oil is taken up in methylene chloride and water. The methylene chloride layer is dried, filtered and concentrated in vacuo leaving an off-white solid which is dissolved in HCl-methanol, filtered and concentrated in vacuo to a yellow oil which is dissolved in ethyl acetate and methanol and recrystallized to give 7.53 grams of a white solid, M.P. 221°-224° C.

1. stirringThe mixture is stirred for an additional one half hour
2. stirringthe mixture stirred overnight
3. filtrationThe reaction mixture is filtered
4. concentrationconcentrated in vacuo
5. customto obtain a yellow oil
6. dry with materialThe methylene chloride layer is dried
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customleaving an off-white solid which
10. filtrationfiltered
11. concentrationconcentrated in vacuo to a yellow oil which
12. dissolutionis dissolved in ethyl acetate
13. custommethanol and recrystallized