Reaktion #216433

Reaktionsgleichung

isopropyltriphenylphosphonium iodide

keto-ester

Methyl 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carbonyl]benzoate

potassium hexamethyldisilazide

toluene

→

desired product 19

Ausbeute 71.0%

Methyl 4-[1-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)-2-methyl-1-propenyl]benzoate

Ausbeute 71.0%

Lösungsmittel

benzene

benzene

dichloromethane hexane

benzene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.DISTILLATIONwas distilled out
2. 2
   workup.WAITAfter 1 h
3. 3
   workup.ADDITIONthe reaction mixture was diluted with 40% ethyl acetate/hexane
4. 4
   Waschenwashed with saturated aqueous NaHCO3 and brine
5. 5
   TrocknenThe organic layer was dried over anhydrous MgSO4
6. 6
   Filtrationfiltered through a plug of silica gel
7. 7
   Einengenconcentrated
8. 8
   Sonstigeto afford a solid

Vorschrift

To a suspension of isopropyltriphenylphosphonium iodide (0.35 g, 0.807 mmol) in 3 mL of benzene under argon at room temperature was added a 0.5M solution of potassium hexamethyldisilazide in toluene (1.8 mL, 0.89 mmol), and the red solution was stirred for 5 min. A solution of keto-ester 3 (0.169 g, 0.481 mmol) in 3 mL of benzene was added, and the red solution was heated to 110° C., while approximately 4 mL of benzene was distilled out. After 1 h, the reaction mixture was diluted with 40% ethyl acetate/hexane and washed with saturated aqueous NaHCO3 and brine. The organic layer was dried over anhydrous MgSO4, filtered through a plug of silica gel, and concentrated to afford a solid. Flash chromatography (40% dichloromethane/hexane) yielded the desired product 19 as a white powder (0.128 g, 71%): Rf 0.44 (50% CH2Cl2 /hexane). The structure of the product was also confirmed using IR, 1H NMR and mass spectroscopy.

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