反应详情

A mixture of 8.1 g (35 mM) of the phenyl carbamate 8 and 2.5 g (23 mM) of 5-amino-2-dimethylaminopyridine in 50 ml of anhydrous DMF was heated at 55° for 3.5 hrs. and then cooled and poured into 200 ml of water. The resulting mixture was extracted with three 100 ml portions of ethyl acetate and the combined extracts were dried (MgSO4), filtered and concentrated to a volume of 50 ml. The precipitate which formed was collected and recrystallized from acetone to give 0.84 of the above urea as tan crystals, m.p. 212°-213° C.

1. temperaturewas heated at 55° for 3.5 hrs
2. temperatureand then cooled
3. extractionThe resulting mixture was extracted with three 100 ml portions of ethyl acetate
4. dry with materialthe combined extracts were dried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated to a volume of 50 ml
7. customThe precipitate which formed
8. customwas collected
9. customrecrystallized from acetone