Reaktion #483772

Reaktionsgleichung

lithium diisopropylamide

5-(benzo[b]thien-2-yl)-2,4-dimethoxybenzaldehyde

3′,5′-dimethoxy-4′-(tert-butyldimethylsiloxy)acetophenone

→

3-[5-(benzo[b]thien-2-yl)2,4-dimethoxyphenyl]-1-(4-ter-butyldimethylsiloxy-3,5-dimethoxyphenyl)-2-propen-1-one

Ausbeute 20.0%

Lösungsmittel

tetrahydrofuran

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwhile chilled
2. 2
   workup.STIRRINGthe mixture was stirred at room temperature for 2 hours
3. 3
   SonstigeUpon quenching with water
4. 4
   Extraktionthe mixture was extracted with dichloromethane
5. 5
   SonstigeThe organic phase was dried
6. 6
   Sonstigeevaporated
7. 7
   SonstigeCrystallization from ethanol

Vorschrift

Ex-59B: To a solution of 3′,5′-dimethoxy-4′-(tert-butyldimethylsiloxy)acetophenone, from Ex-59A (0.5 g, 1.6 mmol) in tetrahydrofuran (10 mL) chilled with ice/water was added lithium diisopropylamide (2 M, 0.8 mL, 1.6 mmol). The mixture was stirred for 20 minutes while chilled. Then 5-(benzo[b]thien-2-yl)-2,4-dimethoxybenzaldehyde, from Ex-6A,(0.48 g, 1.6 mmol) in tetrahydrofuran (6 mL) was added, and the mixture was stirred at room temperature for 2 hours. Upon quenching with water, the mixture was extracted with dichloromethane. The organic phase was dried and evaporated. Crystallization from ethanol gave 0.19 g (20%) of the desired 3-[5-(benzo[b]thien-2-yl)2,4-dimethoxyphenyl]-1-(4-ter-butyldimethylsiloxy-3,5-dimethoxyphenyl)-2-propen-1-one as a yellow solid.

Quelle