反应详情

温度

100 °C

A solution of 600 mg (2.11 mmol) of 2,2,4,4-tetramethyl-6-bromothiochroman (Compound 33) in 1.5 ml of triethylamine was placed in a heavy-walled tube and degassed and then treated under argon with 1.4 g (14.3 mmol) of trimethylsilylacetylene and a powdered mixture of 75 mg (0.39 mmol) of cuprous iodide and 150 mg (0.21 mmol) of bis(triphenylphosphine) palladium (II) chloride. The reaction mixture was degassed again, then placed under argon and the tube was sealed. The mixture was heated at 100 degrees C. for 24 h, allowed to cool to room temperature and then treated with a further 1.4 g (14.3 mmol) of trimethylsilylacetylene and a powdered mixture of 75 mg (0.39 mmol) of cuprous iodide and 150 mg (0.21 mmol) of bis(triphenylphosphine) palladium (II) chloride. The mixture was then degassed, placed under argon and then heated in the sealed tube at 100 degrees C. for 96 h. The mixture was cooled to room temperature and extracted with 3×10 ml of ether. The organic extracts were combined, washed successively with 25 ml of water and 25 ml of saturated sodium chloride solution and then dried (MgSO4). The solvent was removed in vacuo and the residue purified by flash chromatography (silica; hexanes followed by 3% ethyl acetate in hexanes) to give the title compound as a yellow, crystalline solid. PMR (CDCl3): & 0.23 (9H, s), 1.36 (6H, s), 1.39 (6H, s), 1.94 (2H, s), 7.17 (1H, dd, J8.2 Hz, 1.8 Hz), 7.25 (1H, d, J-1.8 Hz), 7.30 (1H, d, J-8.2 Hz). MS exact mass, m/1 302.1519 (calcd. for C18H26S Si, 382.1524).

1. customdegassed
2. customThe reaction mixture was degassed again
3. customthe tube was sealed
4. temperatureto cool to room temperature
5. customThe mixture was then degassed
6. temperatureheated in the sealed tube at 100 degrees C
7. waitfor 96 h
8. temperatureThe mixture was cooled to room temperature
9. extractionextracted with 3×10 ml of ether
10. washwashed successively with 25 ml of water and 25 ml of saturated sodium chloride solution
11. dry with materialdried (MgSO4)
12. customThe solvent was removed in vacuo
13. customthe residue purified by flash chromatography (silica; hexanes followed by 3% ethyl acetate in hexanes)