Réaction #3879

Équation de réaction

N-methylmorpholine

t-butoxycarbonylphenylalanine

N-methylmorpholine

methyl 5-aminopentanoate hydrochloride

isobutylchloroformate

→

title compound

Rendement 96.2%

t-butoxycarbonyl-N-(5-methoxy-5-oxopentyl)-L-phenylalaninamide

Rendement 96.2%

Solvants

dimethylformamide

Conditions de réaction

Traitement

1. 1
   TempératureAfter warming
2. 2
   Autreat ca. -15°
3. 3
   Autrefor about ten minutes
4. 4
   Autrewas recooled to ca. -39°
5. 5
   AutreSolvent and other volatiles were removed by concentration in vacuo
6. 6
   AutreThe residue was triturated with ethyl acetate, which
7. 7
   Lavagewas then washed successively with water, 0.5M potassium bisulfate, water
8. 8
   Séchageagain with 0.5M potassium bisulfate, and then dried over magnesium sulfate
9. 9
   Filtrationfiltered
10. 10
    Concentrationconcentrated to a white solid
11. 11
    AutreAfter collection
12. 12
    Lavagethe white solid was washed thoroughly with Skellysolve B

Mode opératoire

To a cold (ca -30° ), stirred solution of 26.5 g (0.1 mole) of t-butoxycarbonylphenylalanine (BOC-Phe) and 11.2 g (0.1 mole) of N-methylmorpholine in 150 ml of dimethylformamide (DMF) was added dropwise 13.2 ml (0.1 mole) of isobutylchloroformate. After warming and then holding the temperature at ca. -15° for about ten minutes, the solution was recooled to ca. -39°. To the cold mixture was added additional N-methylmorpholine (12.3 ml, ca. 0.11 mole), followed by 18.5 g (0.11 mole) of methyl 5-aminopentanoate hydrochloride. The mixture was allowed to warm to room temperature and to stand overnight. Solvent and other volatiles were removed by concentration in vacuo. The residue was triturated with ethyl acetate, which was then washed successively with water, 0.5M potassium bisulfate, water, and again with 0.5M potassium bisulfate, and then dried over magnesium sulfate, filtered, and concentrated to a white solid. After collection, the white solid was washed thoroughly with Skellysolve B to give 36.4 g of the title compound, m.p. 98°-100°. Recrystallization from ethyl acetate/Skellysolve B afforded analytically pure crystals.

Source