反应详情

温度

90 °C

N-cyano-N'-{2-[(5-methylimidazol-4-yl)-methylthio]-ethyl}-S-methylisothiourea monohydrate (14.35 g; 0.05 mole) is suspended in distilled water (50 ml), stirred and heated. At a bath temperature of 50° C., aqueous methylamine solution (18.5 ml containing 411 g/liter of methylamine, i.e. 0.245 mole equal to 4.9 equivalents) is added. The evolving gas is led to an equipment for destruction (annihilation). The reaction mixture is kept in a bath of 50°-55° C. for 2.5 hours. Initially, the mixture becomes considerably thinner, then, in most cases, N-methyl-N'-{2-[(5-methylimidazol-4-yl)-methylthio]-ethyl}-N"-cyanoguanidine begins to precipitate without appearing of a complete solution. The mixture becomes thicker and eventually the stirring is stopped. After 2.5 hours the mixture is rapidly heated to 90° C. and stirred at this temperature for 30 minutes. The solution should not contain undissolved material. The solution is poured without cooling onto stirred ice (70 g). A clear solution of 0° to 10° C. is formed which becomes turbid and granular, and well-settling crystals separate. The solution is kept in a refrigerator for 2 hours, then filtered and washed with distilled water (2×10 ml). The wet weight of this precipitate is 14.8 g. After drying at 40° C., the dry weight of N-methyl-N'-{2-[(5-methylimidazol-4-yl)-methylthio]-ethyl}-N"-cyanoguanidine H is 12.27 g (90.82%); m.p. 73°-75° C.

1. temperatureheated
2. customThe evolving gas is led to an equipment for destruction (annihilation)
3. customto precipitate
4. stirringstirred at this temperature for 30 minutes
5. additionThe solution is poured
6. temperaturewithout cooling
7. stirringonto stirred ice (70 g)
8. customA clear solution of 0° to 10° C. is formed which
9. customgranular, and well-settling crystals separate
10. waitThe solution is kept in a refrigerator for 2 hours
11. filtrationfiltered
12. washwashed with distilled water (2×10 ml)
13. customAfter drying at 40° C.