Reaction #1469

Reaction equation

ethyl(E)-4-[2-(5,5-dimethyl-5,6,-dihydro-naphthalen-8(7H)-one-2-yl)ethenyl]-benzoate

ethyl(E)-4-[2-(5,6-dihydro-5,5-dimethyl-naphthalen-8(7H)-one-2-yl)ethenyl]benzoate

Compound A2

ethyl(E)-4-[2-(5,6-dihydro-5,5-dimethyl-naphthalen-8(7H)-one-2-yl)ethenyl]benzoate

benzene

benzene

ethyl bromoacetate

→

title compound

(±)Ethyl (E)-4-[2-(5,6,7,8-tetrahydro-5,5-dimethyl-8-hydroxy-8-(methylcarbethoxy)naphthalen-2-yl)ethenyl]benzoate

Conditions

Workup

1. 1
   TemperatureThe resulting mixture was refluxed for 24 h
2. 2
   TemperatureThe reaction was cooled
3. 3
   Filtrationfiltered through celite
4. 4
   WashThe filtrate was washed with 10% HCl, sat. aqueous NaHCO3 and brine
5. 5
   DryingThe organic phase was dried over Na2SO4
6. 6
   Concentrationconcentrated in vacuo
7. 7
   OtherThe crude material was purified by flash chromatography (silica, 10% ethyl acetate in hexane)

Procedure

To a refluxing solution of 0.75 g (11.5 mmol) of granular zinc in 5.0 mL of benzene was added a solution of ethyl(E)-4-[2-(5,5-dimethyl-5,6,-dihydro-naphthalen-8(7H)-one-2-yl)ethenyl]-benzoate (Compound A2) in 5.0 mL of benzene followed by 0.27 g (0.18 mmol) of ethyl bromoacetate. The resulting mixture was refluxed for 24 h. The reaction was cooled, filtered through celite. The filtrate was washed with 10% HCl, sat. aqueous NaHCO3 and brine. The organic phase was dried over Na2SO4 and concentrated in vacuo. The crude material was purified by flash chromatography (silica, 10% ethyl acetate in hexane) to afford the title compound as a white solid.

Source