Reaktion #1731927

Reaktionsgleichung

Water

Trifluoromethanesulfonic anhydride

[6-fluoro-4-(4-hydroxy-benzyl)-3-methyl-naphthalen-2-yl]-acetic acid methyl ester

pyridine

→

[6-fluoro-3-methyl-4-(4-trifluoromethanesulfonyloxy-benzyl)-naphthalen-2-yl]-acetic acid methyl ester

Ausbeute 70.2%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture was then cooled to 4° C
2. 2
   Trocknenthe organic layer was dried over MgSO4
3. 3
   Filtrationfiltered
4. 4
   Einengenconcentrated
5. 5
   EinengenA solution of this crude product in dichloromethane was concentrated over silica gel

Vorschrift

Trifluoromethanesulfonic anhydride (2.6 mL, 15.0 mmol) was added drop-wise to a -6° C. solution of [6-fluoro-4-(4-hydroxy-benzyl)-3-methyl-naphthalen-2-yl]-acetic acid methyl ester (3.9 g, 11.5 mmol) and pyridine (1.4 mL, 17.4 mmol) in dichloromethane (100 mL). The reaction mixture was warmed to room temperature, and stirred for 1 hour. The reaction mixture was then cooled to 4° C. Water (20 mL) was added, and the organic layer was dried over MgSO4, filtered, and concentrated. A solution of this crude product in dichloromethane was concentrated over silica gel, and the resulting silica gel-supported product was subjected to flash chromatography (Analogix SuperFlash™ column, 5%-20% ethyl acetate in hexane) to give 3.8 g (70%) of [6-fluoro-3-methyl-4-(4-trifluoromethanesulfonyloxy-benzyl)-naphthalen-2-yl]-acetic acid methyl ester as a white solid. 1H NMR (300 MHz, DMSO-d6) δ ppm 7.94 (dd, J=8.9, 6.2 Hz, 1 H), 7.79 (s, 1 H), 7.70 (dd, J=12.1, 1.8 Hz, 1 H), 7.37 (d, J=8.8 Hz, 2 H), 7.29-7.38 (m, 1 H), 7.20 (d, J=8.8 Hz, 2 H), 4.53 (s, 2 H), 3.94 (s, 2 H), 3.64 (s, 3 H), 2.29 (s, 3 H).

Quelle