反応 #155404

反応方程式

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

imidazole

TBSCl

HCl

→

desired acid

収率 87.1%

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

収率 87.1%

溶媒

DCM

isopropanol

chloroform

NaOH

反応条件

後処理

1. 1
   温度by heating at 40° C. for 1 hour
2. 2
   温度The reaction mixture was cooled to room temperature
3. 3
   その他was quenched with H2O (3 mL)
4. 4
   その他The organic layer was separated
5. 5
   濃縮was concentrated to dryness
6. 6
   その他to yield a residue, which
7. 7
   温度The reaction was cooled to 0° C.
8. 8
   その他the organic layer was separated
9. 9
   乾燥dried over Na2SO4
10. 10
    濃縮concentrated to dryness

実験手順

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).

出典