Reaction #502126

Reaction equation

N-hydroxyphthalimide

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

1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride

→

title compound

Yield 47.0%

1,3-Dioxobenzo(c)azolidin-2-yl(2S)-2-(6-methoxy(2-naphthyl))propanoate

Yield 47.0%

Solvents

CH2Cl2

DMF

CH2Cl2

Conditions

Workup

1. 1
   Otherthe solvent was evaporated under vacuum
2. 2
   workup.DISSOLUTIONThe residue was then dissolved in EtOAc
3. 3
   Washwashed with brine
4. 4
   Dryingdried over Na2SO4
5. 5
   Filtrationfiltered
6. 6
   OtherThe residue after evaporation of the solvent
7. 7
   Otherwas chromatographed on silica gel eluting with EtOAc:hexane (1:1)

Procedure

A mixture of N-hydroxyphthalimide (7.1 g, 43.4 mmol), (2S)-2-(6-methoxy(2-naphthyl))propanoic acid (naproxen, 10 g, 43.4 mmol) and N,N-dimethylaminopyridine (DMAP, 5.3 g, 43.4 mmol) in CH2Cl2 (70 mL) and DMF (30 mL) at 0° C. was treated with 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (8.3 g, 43.4 mmol) in CH2Cl2 (50 mL). The reaction mixture was stirred at room temperature for 16 hours and the solvent was evaporated under vacuum. The residue was then dissolved in EtOAc, washed with brine, dried over Na2SO4 and filtered. The residue after evaporation of the solvent was chromatographed on silica gel eluting with EtOAc:hexane (1:1) to give the title compound (7.6 g, 47% yield) as a white solid. Mp 110-112° C. 1H NMR (300 MHz, d6-DMSO) δ 7.80-8.06 (m, 7H), 7.50 (dd, J=1.7 and 8.5 Hz, 1H), 7.32-7.37 (m, 1H), 7.20 (dd, J=2.5 and 9.0 Hz, 1H), 4.50 (q, j=7.1 Hz, 1H), 3.89 (s, 3H), 1.64 (d, J=7.1 Hz, 3H). 13C NMR (75 MHz, d6-DMSO) δ 171.2, 161.8, 157.5, 153.0, 135.5, 133.6, 133.5, 129.3, 128.4, 128.2, 127.3, 126.1, 126.0, 124.0, 119.0, 105.8, 55.2, 41.8, 18.6. Mass spectrum (API-TIS) m/z 376 (MH+), 393 (MNH4+).

Source