Reacción #65586

Ecuación de reacción

1-cyclohexyl-3-(2-morpholinoethyl) carbodiimide metho p-toluenesulfonate

triethylamine

thiotetronic acid

cyclododecylbutanoic acid

→

white solid

Rendimiento 33.4%

3-(4-cyclododecyl-1-oxobutyl)-4-hydroxy-2-(5H)thiophenone

Rendimiento 33.4%

Disolventes

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.STIRRINGAfter stirring for 10 minutes
2. 2
   Temperaturato warm to room temperature
3. 3
   workup.STIRRINGis stirred overnight
4. 4
   OtroThe reaction mixture is quenched with 1N HCl
5. 5
   OtroThe layers are separated
6. 6
   Lavadothe aqueous phase is washed once with dichloromethane
7. 7
   LavadoThe combined organic layers are washed twice with aqueous sodium bicarbonate and twice with aqueous 2N HCl
8. 8
   SecadoThe organic phase is then dried over MgSO4
9. 9
   Otrothe dichloromethane evaporated
10. 10
    Otrochromatographed on acidic silica gel using 8% ether/hexanes
11. 11
    workup.DISSOLUTIONdissolved in ether
12. 12
    Lavadowashed with 1N HCl
13. 13
    Otrodried
14. 14
    Otroevaporated

Procedimiento

To a dry flask under N2 atmosphere at 0° C. is added 1.31 g (11.3 mmol) of thiotetronic acid in 40 mL of dry dichloromethane followed by 1.42 mL (10.2 mmol) of triethylamine and 0.38 g (3.1 mmol) of 4-dimethylaminopyridine. After stirring at 0° C. for 5 minutes, 2.6 g (10.2 mmol) of cyclododecylbutanoic acid is added followed by 4.8 g (11.3 mmol) of 1-cyclohexyl-3-(2-morpholinoethyl) carbodiimide metho p-toluenesulfonate. After stirring for 10 minutes, the reaction mixture is allowed to warm to room temperature and is stirred overnight. The reaction mixture is quenched with 1N HCl. The layers are separated and the aqueous phase is washed once with dichloromethane. The combined organic layers are washed twice with aqueous sodium bicarbonate and twice with aqueous 2N HCl. The organic phase is then dried over MgSO4 and the dichloromethane evaporated. The residue is flash chromatographed on acidic silica gel using 8% ether/hexanes, dissolved in ether, washed with 1N HCl, dried and evaporated to give 1.2 g of a white solid: m.p. 62°-69° C.; IR; NMR (CDCl3) δ 1.2-1.4 (m, 10H), 1.5 (s, 4H), 1.65 (m, 2H), 2.9 (t, 2H, J=7 Hz), 3.96 and 3.75 (s, 2H); MS

Fuente