تفاعل #9202

معادلة التفاعل

Et2O

2-amino-7-oxo-4,5,6,7-tetrahydro-benzothiazole

2-Amino-7-oxo-4, 5, 6, 7-tetrahydro-benzothiazole

triethylamine

ethyl isocyanate

→

4

المردود 85.0%

1-(7-Oxo-4,5,6,7-tetrahydro-2-benzothiazolyl)-3-ethyl-urea

المردود 85.0%

المذيبات

DMF

ظروف التفاعل

المعالجة

1. 1
   workup.DISTILLATIONThe DMF solvent was distilled off under reduced pressure
2. 2
   أخرىA sticky brown residue was obtained
3. 3
   ترشيحwas filtered off
4. 4
   غسيلwashed with more Et2O (50 mL)
5. 5
   أخرىThe light brown colored solid was dried under vacuum

الإجراء التجريبي

A solution of 2-amino-7-oxo-4,5,6,7-tetrahydro-benzothiazole 3 (11.56 g, 68.7 mmol) in anhydrous DMF (200 mL) was treated with triethylamine (19.2 mL, 137 mmol, 2.0 eq) and ethyl isocyanate (10.9 nL, 137 mmol, 2.0 eq). The reaction mixture was heated at about 90° C. with stirring for about 3 hours. The DMF solvent was distilled off under reduced pressure. A sticky brown residue was obtained. Treatment with Et2O (100 mL) gave a precipitate, which was filtered off and washed with more Et2O (50 mL). The light brown colored solid was dried under vacuum to give 13.97 g (85%) of 4. The material was used in the following synthesis without further purification. 1H NMR (DMSO) δ 10.95 (br s, 1H, NH), 6.66 (br s, 1H, NH), 3.16 (p, 2H, J=7.2 Hz, CH2), 2.79 (t, 2H, J=6.1 Hz, CH2), 2.45 (t, 2H, J=6.5 Hz, CH2), 2.05 (p, 2H, J=6.4 Hz, CH2), 1.07 (t, 3H, J=7.2 Hz, CH3); LC/MS 240 (MH+); RP-HPLC RT 2.27 minutes.

المصدر