反応 #1772018

反応方程式

ClCO2Me

(R)-tert-butyl 2-amino-2-phenylacetate HCl

diisopropylethylamine

→

(R)-tert-butyl 2-(methoxycarbonylamino)-2-phenylacetate

収率 71.6%

溶媒

THF

反応条件

後処理

1. 1
   その他The volatile component was removed in vacuo
2. 2
   その他the residue was partitioned between water (100 mL) and ethyl acetate (200 mL)
3. 3
   洗浄The organic layer was washed with 1N HCl (25 mL) and saturated NaHCO3 solution (30 mL)
4. 4
   乾燥dried (MgSO4)
5. 5
   ろ過filtered
6. 6
   濃縮concentrated in vacuo
7. 7
   その他The resultant colorless oil was triturated from hexanes
8. 8
   ろ過filtered
9. 9
   洗浄washed with hexanes (100 mL)

実験手順

ClCO2Me (3.2 mL, 41.4 mmol) was added dropwise to a cooled (ice/water) THF (410 mL) semi-solution of (R)-tert-butyl 2-amino-2-phenylacetate/HCl (9.877 g, 40.52 mmol) and diisopropylethylamine (14.2 mL, 81.52 mmol) over 6 min, and stirred at similar temperature for 5.5 hours. The volatile component was removed in vacuo, and the residue was partitioned between water (100 mL) and ethyl acetate (200 mL). The organic layer was washed with 1N HCl (25 mL) and saturated NaHCO3 solution (30 mL), dried (MgSO4), filtered, and concentrated in vacuo. The resultant colorless oil was triturated from hexanes, filtered and washed with hexanes (100 mL) to provide (R)-tert-butyl 2-(methoxycarbonylamino)-2-phenylacetate as a white solid (7.7 g). 1H NMR (DMSO-d6, δ=2.5 ppm, 400 MHz): 7.98 (d, J=8.0, 1H), 7.37-7.29 (m, 5H), 5.09 (d, J=8, 1H), 3.56 (s, 3H), 1.33 (s, 9H). LC (Cond. I): RT=1.53 min; ˜90% homogeneity index; LC/MS: Anal. Calcd. for [M+Na]+ C14H19NNaO4: 288.12. found 288.15.

出典