تفاعل #9214

معادلة التفاعل

1-(7-hydroxy-2-benzothiazolyl)-3-ethyl-urea

1-(7-Hydroxy-2-benzothiazolyl)-3-ethyl-urea

nitronium tetrafluoroborate

→

desired compound 17

المردود 10.4%

1-(7-Hydroxy-6-nitro-2-benzothiazolyl)-3-ethyl-urea

المردود 10.4%

المذيبات

acetonitrile

diethyl ether

acetonitrile

ظروف التفاعل

المعالجة

1. 1
   أخرىto get an orange solution
2. 2
   workup.STIRRINGThe reaction mixture was stirred at about 20° C. for about 15 minutes
3. 3
   غسيلby washing with saturated sodium bicarbonate solution (1.5 mL)
4. 4
   استخلاصThe organic extract
5. 5
   تركيزwas concentrated
6. 6
   workup.DISSOLUTIONdissolved in methanol (2 mL)
7. 7
   أخرىLC/MS purification
8. 8
   أخرىwas followed by flash chromatography purification on silica (methylene chloride/methanol=40/1)

الإجراء التجريبي

To a solution of 2-methylpyridone (0.020 mL, 0.20 mmol, 1.2 eq) in anhydrous acetonitrile (0.5 mL), nitronium tetrafluoroborate (0.045 g, 0.32 mmol, 1.9 eq) was added. The suspension was stirred at about 20° C. for about 5 minutes to get an orange solution. The solution was then transferred to a suspension of 1-(7-hydroxy-2-benzothiazolyl)-3-ethyl-urea 8 (0.040 g, 0.17 mmol) in acetonitrile (0.5 mL). The reaction mixture was stirred at about 20° C. for about 15 minutes, then taken up in diethyl ether (8 mL), and neutralized by washing with saturated sodium bicarbonate solution (1.5 mL). The organic extract was concentrated and dissolved in methanol (2 mL). LC/MS purification was followed by flash chromatography purification on silica (methylene chloride/methanol=40/1) to afford 0.005 g (10%) of the desired compound 17. 1H NMR (DMSO) δ 11.20 (br s, 1H, NH), 8.02 (d, 1H, J=9.0 Hz, ArH), 7.23 (d, 1H, J=7.5 Hz, ArH), 6.78 (br s, 1H, NH), 3.20 (m, 2H, CH2), 1.10 (t, 3H, J=7.2 Hz, CH3). LC/MS 283 (MH+); RP-HPLC RT 2.74 minutes.

المصدر