Reaktion #42207

Reaktionsgleichung

alcohol

(±)-2,3-dihydronaphtho[1,2-b]furan-2-ylmethanol

(±)-2,3-dihydronaphtho[1,2-b]furan-2-ylmethyl 4-methylbenzenesulfonate

triethylamine

p-toluenesulfonyl chloride

tosylate

sodium azide

→

(±)-2-(azidomethyl)-2,3-dihydronaphtho[1,2-b]furan

Ausbeute 71.0%

Lösungsmittel

water

dimethylsulfoxide

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled to room temperature
2. 2
   Extraktionextracted with diethyl ether (2×100 mL)
3. 3
   WaschenThe combined organic extracts were washed with water (4×75 mL), saturated aqueous sodium chloride (75 mL)
4. 4
   Trocknendried (magnesium sulfate)
5. 5
   Sonstigethe solvent was removed in vacuo
6. 6
   Sonstigeto provide a crude oil
7. 7
   SonstigePurification by flash column chromatography (silica, ethyl acetate:hexanes 1:9)

Vorschrift

Treatment of (±)-tert-butyl(2,3-dihydronaphtho[1,2-b]furan-2-ylmethoxy)dimethylsilane (2.70 g; 8.59 mmol) with tetrabutylammonium fluoride (9.4 mL, 1.0 M solution in tetrahydrofuran) generally according to the procedure described for Intermediate 6 gave (±)-2,3-dihydronaphtho[1,2-b]furan-2-ylmethanol. Treatment of the alcohol with p-toluenesulfonyl chloride (1.64 g, 8.59 mmol), 4-(dimethylamino)pyridine (0.105 g, 0.86 mmol), and triethylamine (1.67 g, 12.89 mmol) generally according to the procedure described for Intermediate 14 provided (±)-2,3-dihydronaphtho[1,2-b]furan-2-ylmethyl 4-methylbenzenesulfonate. To a solution of the tosylate in dimethylsulfoxide (50 mL) was added sodium azide (0.558 g, 8.59 mmol) and the reaction mixture was allowed to stir at 70° C. for 12 h, cooled to room temperature, diluted with water (200 mL) and extracted with diethyl ether (2×100 mL). The combined organic extracts were washed with water (4×75 mL), saturated aqueous sodium chloride (75 mL), dried (magnesium sulfate), and the solvent was removed in vacuo to provide a crude oil. Purification by flash column chromatography (silica, ethyl acetate:hexanes 1:9) provided 1.38 g (71%) of (±)-2-(azidomethyl)-2,3-dihydronaphtho[1,2-b]furan as a colorless oil. Rf=0.46 (silica, ethyl acetate:hexanes 1:9); Anal. calcd. for C13H11N3O.0.1H2O: C, 68.77; H, 4.97; N, 18.51. Found: C, 68.4; H, 4.62; N, 18.12.

Quelle