Réaction #155404

Équation de réaction

N-Boc-1(R)-amino-2(S)-hydroxy-cyclopentane-4(S)-carboxylic acid methyl ester

imidazole

TBSCl

HCl

→

desired acid

Rendement 87.1%

N-Boc-1(R)-amino-2(S)-tert-butyldimethylsilyloxy-cyclopentane-4(S)-carboxylic acid

Rendement 87.1%

Solvants

DCM

isopropanol

chloroform

NaOH

Conditions de réaction

Traitement

1. 1
   Températureby heating at 40° C. for 1 hour
2. 2
   TempératureThe reaction mixture was cooled to room temperature
3. 3
   Autrewas quenched with H2O (3 mL)
4. 4
   AutreThe organic layer was separated
5. 5
   Concentrationwas concentrated to dryness
6. 6
   Autreto yield a residue, which
7. 7
   TempératureThe reaction was cooled to 0° C.
8. 8
   Autrethe organic layer was separated
9. 9
   Séchagedried over Na2SO4
10. 10
    Concentrationconcentrated to dryness

Mode opératoire

To a stirring solution of N-Boc-1(R)-amino-2(S)-hydroxy-cyclopentane-4(S)-carboxylic acid methyl ester (0.622 g, 2.40 mmol) in DCM (1.9 mL) was added imidazole (0.164 g, 2.41 mmol), DMAP (0.047 g, 0.35 mmol) and TBSCl (0.363 g, 2.40 mmol) and the reaction was stirred at room temperature for 18 hours, followed by heating at 40° C. for 1 hour. The reaction mixture was cooled to room temperature, and was quenched with H2O (3 mL). The organic layer was separated and was concentrated to dryness to yield a residue, which was dissolved in isopropanol (6 mL) and 1M NaOH (2.9 mL), and the reaction was heated at 60° C. for 1 hour. The reaction was cooled to 0° C. and slowly acidified to pH 3 with 1M HCl (3 mL). After adding chloroform (18 mL), the organic layer was separated, dried over Na2SO4, and concentrated to dryness to yield the desired acid (0.75 g, 2.09 mmol, 87.1% yield).

Source