反应详情

温度

-20 °C

A suspension of 31.95 g (0.15 mole) of 2-iminoimidazolidine monohydroiodide in 400 ml THF was treated with 11.99 g (0.15 mole) 50% NaOH solution and stirred for 0.5 hour. Twenty grams of anhydrous Na2SO4 were added and the mixture stirred an additional 0.5 hour. After cooling to -20° C. (it was necessary to maintain a temperature of -20° C. at all times when in the free base form) under N2, a solution of 9.99 g (0.075 mole) of 3-methylphenyl isocyanate in 125 ml THF was added dropwise over a 3-hour period, maintaining a temperature of -20° C. The mixture was stirred an additional hour, then the inorganics were filtered off and the solvent was removed in vacuo, cold, to yield a yellow oil, which was stirred in cold brine and extracted with 3×150 ml portions of cold CH2Cl2. The combined CH2Cl2 extracts were dried over anhydrous K2CO3 and filtered. The filtrate was acidified to pH<3 with excess ethereal HCl, adding MeOH to dissolve solids which formed upon acidification. The solution was stored in a freezer overnight. The solvent and excess HCl were removed in vacuo to leave a yellow-orange oil, which solidified when washed with Et2O. The solid was recrystallized from MeOH/Et2O to yield 11.11 g of impure product which was converted to the free base and then back to the HCl salt, and recrystallized from MeOH/Et2O to yield 7.99 g (41.8%) of pure hydrochloride salt, a white solid, m.p. 195°-196.5° C. (dec.).

1. stirringthe mixture stirred an additional 0.5 hour
2. temperatureto maintain a temperature of -20° C. at all times when in the free base form) under N2
3. temperaturemaintaining a temperature of -20° C
4. stirringThe mixture was stirred an additional hour
5. filtrationthe inorganics were filtered off
6. customthe solvent was removed in vacuo
7. customcold, to yield a yellow oil, which
8. extractionextracted with 3×150 ml portions of cold CH2Cl2
9. dry with materialThe combined CH2Cl2 extracts were dried over anhydrous K2CO3
10. filtrationfiltered
11. additionadding MeOH
12. dissolutionto dissolve solids which
13. customformed upon acidification
14. waitThe solution was stored in a freezer overnight
15. customThe solvent and excess HCl were removed in vacuo
16. customto leave a yellow-orange oil, which
17. washwashed with Et2O
18. customThe solid was recrystallized from MeOH/Et2O