Réaction #1312

Équation de réaction

trimethylsilyl acetylene

6-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one

Compound H

6-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one

K2CO3

→

title compound

6-Ethynyl-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one

Solvants

triethylamine

methanol

Conditions de réaction

Traitement

1. 1
   AutreThe solution mixture was flushed with argon for 5 minutes
2. 2
   AutreThe reaction mixture was sealed in a pressure tube
3. 3
   Autreplaced in a preheated oil bath
4. 4
   FiltrationThe reaction mixture was then filtered through celite
5. 5
   Lavagewashed with Et2O
6. 6
   Concentrationthe filtrate concentrated in vacuo
7. 7
   Autreto give crude 6-(2-trimethylsilyl)ethynyl-3,4-dihydro-4,4-di-methyl-naphthalen-1(2H)-one
8. 8
   Filtrationfiltered
9. 9
   ConcentrationThe filtrate was concentrated in vacuo
10. 10
    workup.ADDITIONdiluted with Et2O (100 ml)
11. 11
    Lavagewashed with water (10 ml), 10% HCl (10 ml) and brine (10 ml)
12. 12
    Séchagedried over MgSO4
13. 13
    Concentrationconcentrated in vacuo
14. 14
    AutrePurification by column chromatography (silica, 10% EtOAc-hexane)

Mode opératoire

To a solution (flushed for 15 minutes with a stream of argon) of 13.55 g (53.8 mmol) of 6-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound H) in 280 ml of triethylamine was added 1.87 g (2.66 mmol) of bis(triphenylphosphine)palladium(II) chloride and 0.53 g (2.66 mmol) of cuprous iodide. The solution mixture was flushed with argon for 5 minutes and then 100 ml (938.7 mmol) of trimethylsilyl acetylene was added. The reaction mixture was sealed in a pressure tube and placed in a preheated oil bath (100° C.) for 24 hours. The reaction mixture was then filtered through celite, washed with Et2O and the filtrate concentrated in vacuo to give crude 6-(2-trimethylsilyl)ethynyl-3,4-dihydro-4,4-di-methyl-naphthalen-1(2H)-one. To a solution of this crude TMS-acetylenic compound in 50 ml of methanol was added 2.8 g (20.3 mmol) of K2CO3. The mixture was stirred for 8 hours at ambient temperature and then filtered. The filtrate was concentrated in vacuo, diluted with Et2O (100 ml), washed with water (10 ml), 10% HCl (10 ml) and brine (10 ml), dried over MgSO4 and concentrated in vacuo. Purification by column chromatography (silica, 10% EtOAc-hexane) yielded the title compound as a white solid.

Source