Reaktion #568386

Reaktionsgleichung

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

Lösungsmittel

potassium carbonate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextracted with ether (2×)
2. 2
   WaschenThe organic phase was washed with brine
3. 3
   Trocknendried over MgSO4
4. 4
   Einengenconcentrated in vacuo
5. 5
   SonstigeThe crude product was purified by flash chromatography (silica, 10% ethyl acetate in hexane)

Vorschrift

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. 1H NMR (CDCl3): δ 1.29 (s, 6H), 1.39 (t, J=7.1 Hz, 3H), 1.83 (m, 2H), 2.00 (m, 1H), 2.09 (m, 1H), 2.62 (m, 2H), 2.74 (m, 2H), 3.17 (m, 2H), 4.36 (q, J=7.1 Hz, 2H), 7.09 (d, J=16.4 Hz, 1H), 7.20 (d, J=16.4 Hz, 1H), 7.30 (d, J=8.2 Hz, 1H), 7.41 (dd, J=1.9, 8.2 Hz, 1H), 7.55 (d, J=8.4 Hz, 2H), 8.00 (d, J=8.4 Hz, 1H), 8.10 (d, J=1.9 Hz, 2H).

Quelle