Hydrogen Peroxide → 2-Methoxy-5,6,7,8-tetrahydronaphthalen-1-ol

To a well-stirred solution of 6-methoxy-1,2,3,4-tetrahydronapthalene (14.05 g, 86.67 mmol) in sec-butyllithium (100 mL, 110 mmol) at 0° C., under nitrogen, was added freshly distilled N,N,N′,N′-tetramethylethylenediamiene (13.61 mL) dropwise. After the addition was complete, the reaction mixture was stirred at room temperature for 1 h. Then, the reaction mixture was cooled again to 0° C. and trimethyl borate (12.55 mL, 110 mmol) was added dropwise and the reaction mixture was stirred for 1 h at room temperature. The reaction mixture was cooled back to 0° C. and 7 mL of glacial acetic acid was added dropwise, the reaction mixture was let to cool to 0° C. and then 35% wt. hydrogen peroxide in water (15 mL) was added dropwise. The reaction mixture was then allowed to stir at room temperature for 12 h. Saturated ammonium chloride (100 mL) was added. The organic phase was separated and collected, and the aqueous phase was extracted with ether. The combined organic phases were washed with brine (if necessary) and dried over anhydrous sodium sulfate, filtered, concentrated in vacuo. Purification by flash column chromatography (silica gel, 2:98 EtOAc:Hexanes) yielded 3.5 g (23%) of 33 along with 9.7 g (63.1%) of 7-hydroxy-6-methoxy-(1,2,3,4-tetrahydro)naphthalene (obtained in 5:95 EtOAc:Hexanes). Rf value for 33 is 0.48 (15:85 EtOAc:Hexanes), for 7-hydroxy-6-methoxy-1-tetrahydronapthalene 0.37.

1. additionAfter the addition
2. temperatureThen, the reaction mixture was cooled again to 0° C.
3. stirringthe reaction mixture was stirred for 1 h at room temperature
4. temperatureThe reaction mixture was cooled back to 0° C.
5. temperatureto cool to 0° C.
6. stirringto stir at room temperature for 12 h
7. customThe organic phase was separated
8. customcollected
9. extractionthe aqueous phase was extracted with ether
10. washThe combined organic phases were washed with brine (if necessary)
11. dry with materialdried over anhydrous sodium sulfate
12. filtrationfiltered
13. concentrationconcentrated in vacuo
14. customPurification by flash column chromatography (silica gel, 2:98 EtOAc:Hexanes)

ORD-Eintrag

ord-aa1b4a74cdfb4cb7a1dd2d950993dc09

Quelldatensatz

uspto-grants-2008_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07429681B2