Reaktion #216432

Reaktionsgleichung

potassium hexamethyldisilazide

toluene

keto-ester

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

benzene

benzene

NaHCO3

→

desired product 16

Ausbeute 80.0%

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

Ausbeute 80.0%

Lösungsmittel

dichloromethane hexane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe orange solution was stirred for 1 h at room temperature
2. 2
   Extraktionextracted with 40% ethyl acetate/hexane
3. 3
   TrocknenThe combined organic layers were dried over anhydrous MgSO4
4. 4
   Filtrationfiltered through a plug of silica gel
5. 5
   Einengenconcentrated
6. 6
   Sonstigeto afford a solid

Vorschrift

To a suspension of methyltriphenylphosphonium bromide (0.78 g, 2.18 mmol) in 5 mL of benzene under argon at room temperature was added a 0.5M solution of potassium hexamethyldisilazide in toluene (4.4 mL, 2.2 mmol), and the yellow solution was stirred for 5 min. A solution of keto-ester 3 (0.51 g, 1.455 mmol) in 7 mL of benzene was added, and the orange solution was stirred for 1 h at room temperature. The reaction mixture was poured into saturated aqueous NaHCO3 and extracted with 40% ethyl acetate/hexane. The combined organic layers were dried over anhydrous MgSO4, filtered through a plug of silica gel, and concentrated to afford a solid. Flash chromatography (30% dichloromethane/hexane) yielded the desired product 16 as a white solid (0.405 g, 80%): m.p. 117°-118° C.; Rf 0.2 (25% CH2Cl2 /hexane). The structure of the product was also confirmed using IR, 1H NMR and mass spectroscopy.

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