Réaction #1468

Équation de réaction

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

1,3-propanedithiol

methylene chloride

→

title compound

Ethyl (E)-4-[-2-(5,6,7,8-tetrahydro-5,5-dimethyl-8-(1,3-dithian-2-yl)naphthalen-2-yl)ethenyl]benzoate

Solvants

potassium carbonate

Conditions de réaction

Traitement

1. 1
   Extractionextracted with ether (2×)
2. 2
   LavageThe organic phase was washed with brine
3. 3
   Séchagedried over MgSO4
4. 4
   Concentrationconcentrated in vacuo
5. 5
   AutreThe crude product was purified by flash chromatography (silica, 10% ethyl acetate in hexane)

Mode opératoire

To a cold solution (0° C.) of 140 mg (0.40 mmol) of ethyl(E)-4-[2-(5,5-dimethyl-5,6,-dihydro-naphthalen-8(7H)-one-2-yl)ethenyl]-benzoate (Compound A2), in 6.0 mL of methylene chloride was added dropwise 130 mg (0.12 mL, 1.2 mmol) of 1,3-propanedithiol and 0.17 g (0.15 mL, 102 mmol) of borontrifluoride diethyl etherate. The reaction stirred between 0° C. and room temperature for 4 h. The mixture was diluted with aqueous sat. potassium carbonate, and extracted with ether (2×). The organic phase was washed with brine, dried over MgSO4 and then concentrated in vacuo. The crude product was purified by flash chromatography (silica, 10% ethyl acetate in hexane) to afford the title compound as a solid.

Source