反応 #66046

反応方程式

52

Methyl (2R)-2-acetamido-3-(4-allyloxyphenyl)propanoate

lithium hydroxide monohydrate

→

title compound

収率 88.0%

(2R)-2-Acetamido-3-(4-Allyloxyphenyl)propanoic acid

収率 88.0%

溶媒

water

THF water

反応条件

後処理

1. 1
   その他the THF was removed in vacuo
2. 2
   抽出The aqueous layer was extracted with diethyl ether (40 mL)
3. 3
   その他to remove unreacted
4. 4
   抽出the resulting precipitate was extracted with DCM (3×40 mL)
5. 5
   乾燥The combined DCM fractions were dried
6. 6
   その他evaporated

実験手順

To a solution of 52 (900 mg, 3.25 mmol) in THF/water, 3:1 (10 mL) was added lithium hydroxide monohydrate (273 mg, 6.5 mmol), and the resulting suspension was allowed to stir for 16 h. The reaction mixture was diluted with water (30 mL) and the THF was removed in vacuo. The aqueous layer was extracted with diethyl ether (40 mL) to remove unreacted starting material. The aqueous phase was acidified with 10% HCl and the resulting precipitate was extracted with DCM (3×40 mL). The combined DCM fractions were dried and evaporated to yield the title compound (750 mg, 2.85 mmol, 88%) as a white solid. [α]D23 −23.2 (c. 0.1, EtOH). Mp 75° C. 1HNMR (D6 acetone, 300 MHz): δ 7.27 (d, J=7.8 Hz, 1H, NH); 7.17 (d, J=8.7 Hz, 2H, ArH2′ and ArH6′); 6.86 (d, J=8.7 Hz, 21H, ArH3′ and ArH5′); 6.06 (m, 1H, H2″); 5.40 (dd J=1.5 Hz, 17.5 Hz, 1H, H3a″); 5.23 (dd, J=1.5, 10.5 Hz, 1H, H3b″); 4.67 (dd, J=5.1, 8.1, 10.5 Hz 1H, H2); 4.53 (d, J=5.1 Hz, 2H, H1″); 3.11 (dd, J=5.4, 14.1 Hz, 1H; 3Ha); 2.93 (dd, J=8.1, 14.1, 1H, 3Hb); 1.89 (s, 31H, NCOCH3). Mass Spectrum (CI, +ve) m/z 264 (100%) [MH+]. HRMS calcd for C14H18NO4 264.123583, found 264.123770.

出典