Reaktion #2640

Reaktionsgleichung

tert-butyl methyl ether

4-tert-butyldimethylsiloxy-2-cyclopentenone

MgBr2

lithium aluminum hydride

lithium aluminum hydride

→

title compound

Ausbeute 64.4%

cis-4-tert-butyldimethylsilyloxy-2-cyclopentenol

Ausbeute 64.4%

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeovernight
2. 2
   Sonstigeat room temperature
3. 3
   workup.STIRRINGthe reaction is stirred for 2 hours
4. 4
   SonstigeThe reaction is then quenched by slow addition of 1N NaOH (5 mL)
5. 5
   Filtrationfollowed by filtration through diatomaceous earth
6. 6
   TrocknenThe filtrate is dried over anhydrous magnesium sulfate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated under vacuum

Vorschrift

A stirred solution of 4-tert-butyldimethylsiloxy-2-cyclopentenone (2.0 g, 9.42 mmol) in anhydrous toluene (15 mL) under an atmosphere of argon is treated with MgBr2 (3.5 g, 19.0 mol). The mixture is cooled to -25° C. and treated with lithium aluminum hydride (178 mg, 4.69 mmol) in one portion, followed by addition of anhydrous tert-butyl methyl ether (3.0 mL). The reaction is stirred at -20° C. for 2 hours and then overnight at room temperature. Additional lithium aluminum hydride (178 mg, 4.69 mmol) is added at room temperature and the reaction is stirred for 2 hours. The reaction is then quenched by slow addition of 1N NaOH (5 mL) followed by filtration through diatomaceous earth. The filtrate is dried over anhydrous magnesium sulfate, filtered and concentrated under vacuum to provide the title compound (1.3 g); cis/trans/1-2 +1-4 addition, 90/3/7.

Quelle