Reaction #42346

Reaction equation

Boc-L-alanine

isobutylamine

diisopropylethylamine

HOBt

→

title compound

N1-Isobutyl-L-alaninamide

Solvents

ethyl acetate

EDC

DMF

Conditions

Workup

1. 1
   Washwashed with 1 N hydrochloric acid, saturated sodium bicarbonate, and brine
2. 2
   Dryingdried (magnesium sulfate)
3. 3
   Filtrationfiltered
4. 4
   Concentrationconcentrated under reduced pressure
5. 5
   workup.DISSOLUTIONThe residue is redissolved in 4N hydrochloric acid in dioxane (30 mL)
6. 6
   workup.STIRRINGstirred for 2 h
7. 7
   ConcentrationThe solution is concentrated under reduced pressure
8. 8
   workup.DISSOLUTIONdissolved in chloroform
9. 9
   Washwashed with 1 N NaOH (aq)
10. 10
    ExtractionThe aqueous layer is extracted with chloroform
11. 11
    Dryingthe pooled organics are dried (sodium sulfate)
12. 12
    Filtrationfiltered
13. 13
    Concentrationconcentrated under reduced pressure

Procedure

Boc-L-alanine (5.0 g, 26.4 mmol), isobutylamine (2.9 mL, 29.1 mmol), diisopropylethylamine (11.5 mL, 66 mmol), and HOBt (3.6 g, 26.4 mmol) in anhydrous DMF (15 mL) is stirred 15 min. EDC is added, and the reaction is stirred at room temperature 16 h. The reaction is diluted in ethyl acetate and washed with 1 N hydrochloric acid, saturated sodium bicarbonate, and brine, dried (magnesium sulfate), filtered, and concentrated under reduced pressure. The residue is redissolved in 4N hydrochloric acid in dioxane (30 mL) and stirred for 2 h. The solution is concentrated under reduced pressure, dissolved in chloroform and washed with 1 N NaOH (aq). The aqueous layer is extracted with chloroform, and the pooled organics are dried (sodium sulfate), filtered, and concentrated under reduced pressure to give the title compound. ESI MS m/z 145.2 [M+H]+.

Source