Reacción #1771996

Ecuación de reacción

dichloroacetic acid

Boc-norvalinol

toluene

EDC

→

Boc-norvalinal

Disolventes

dimethylsulfoxide

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONAfter addition
2. 2
   Temperaturato warm to room temperature over a period of 2 h
3. 3
   ConcentraciónThe reaction mixture was concentrated
4. 4
   Otroto remove the toluene
5. 5
   workup.DISSOLUTIONdissolved in ethyl acetate
6. 6
   LavadoThe solution was washed successively with 1N sodium bisulfate, saturated sodium bicarbonate and brine
7. 7
   Secadodried over sodium sulfate
8. 8
   Filtraciónfiltered
9. 9
   Concentraciónconcentrated

Procedimiento

To Boc-norvalinol (7.77 g, 38 mmol), in anhydrous dimethylsulfoxide (153 mL) and toluene (153 mL) was added EDC (73.32 g, 382 mmol). After the solution was cooled to 0° C., dichloroacetic acid (15.8 mL, 191 mmol) was added dropwise. After addition was complete, the reaction was stirred for 15 min. The solution was allowed to warm to room temperature over a period of 2 h. The reaction mixture was concentrated to remove the toluene, then dissolved in ethyl acetate. The solution was washed successively with 1N sodium bisulfate, saturated sodium bicarbonate and brine, dried over sodium sulfate, filtered and concentrated to afford crude Boc-norvalinal which was used directly in the next step. TLC Rf=0.84 (40% ethyl acetate/hexanes).

Fuente