反応 #502127

反応方程式

(2S)-2-(6-methoxy(2-naphthyl))propanoic acid

tert-butyl N-(2-hydroxyethyl)carbamate

1,3-dicyclohexylcarbodiimide

→

title compound

収率 82.4%

2-((tert-Butoxy)carbonylamino)ethyl(2S)-2-(6-methoxy(2-naphthyl))propanoate

収率 82.4%

溶媒

CH2Cl2

反応条件

後処理

1. 1
   その他The byproduct, dicyclohexyl urea, was removed by filtration
2. 2
   濃縮The filtrate was concentrated
3. 3
   workup.DISSOLUTIONdissolved in EtOAc (50 mL)
4. 4
   温度cooled in a dry-ice bath
5. 5
   その他to precipitate the remaining dicyclohexyl urea
6. 6
   ろ過filtered
7. 7
   濃縮The filtrate was concentrated
8. 8
   workup.DISSOLUTIONdissolved in CH2Cl2 (15 mL)
9. 9
   その他precipitated
10. 10
    その他The solid was dried under vacuum

実験手順

A solution of (2S)-2-(6-methoxy(2-naphthyl))propanoic acid (naproxen, 7.60 g, 33.0 mmol), tert-butyl N-(2-hydroxyethyl)carbamate (5.30 g, 32.9 mmol), N,N-dimethylaminopyridine (DMAP, 0.35 g, 2.86 mmol) and 1,3-dicyclohexylcarbodiimide (6.80 g, 33.0 mmol) in CH2Cl2 (200 mL) was stirred at ambient temperature overnight. The byproduct, dicyclohexyl urea, was removed by filtration. The filtrate was concentrated, dissolved in EtOAc (50 mL) and then cooled in a dry-ice bath to precipitate the remaining dicyclohexyl urea and then filtered. The filtrate was concentrated, dissolved in CH2Cl2 (15 mL) and hexane (200 mL) and then stirred until the product precipitated. The solid was dried under vacuum to give the title compound (10.12 g, 82% yield). Mp 82-84° C. 1H NMR (300 MHz, CDCl3) δ 7.72-7.65 (m, 3H), 7.42-7.38 (m, 1H), 7.16-7.11 (m, 2H), 5.05 (br, 1H), 4.13 (t, J=5.3 Hz, 2H), 3.91 (s, 3H), 3.87 (q, J=7.1 Hz, 1H), 3.30 (br. q, 2H), 1.58 (d, J=7.1 Hz, 3H), 1.45 (s, 9H). 13C NMR (75 MHz, CDCl3) δ 174.4, 157.6, 155.6, 135.4, 133.6, 129.2, 128.8, 127.1, 126.0, 125.8, 119.0, 105.5, 79.3, 63.7, 55.2, 45.2, 39.5, 28.2, 18.3. Mass spectrum (API-TIS) m/z 374 (MH)+. Anal. calcd. for C21H27NO5: C, 67.54; H, 7.29; N, 3.75. Found: C, 67.43; H, 7.16; N, 3.66.

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