Trimethylsilylacetylene → Trimethylsilyl (4,4,7-trimethyl-thiochroman-6-yl) ethyne

Participants

Reaction Conditions

Reaction Steps

A mixture of 624 mg (3.0 mmol) of 4,4,7-trimethyl-6-bromothiochroman (Compound 66) 314 mg (3.2 mmol) of trimethylsilyl acetylene, 40 mg (0.21 mmol) of cuprous iodide, 80 mg (0.11 mmol) of bis (triphenylphosphin) palladium (II) chloride and 1 ml of triethylamine was degassed under nitrogen and heated in a sealed tube at 85 degrees C for 15 h. The mixture was then treated with a further 20 mg (0.11 mmol) of cuprous iodide and 40 mg (0.06 mmol) of the palladium (II) catalyst. The mixture was then heated under a nitrogen atmosphere in the sealed tube at 100 degrees C for a further 64 h. The triethylamine was then removed under vacuum and the residue purified by flash chromatography (silica; hexanes) to give the title compound as a yellow oil. PMR (CDCl3): & 0.28 (9H, s), 1.30 (6H, s), 1.88-1.97 (2H, m), 2.33 (3H, s), 2.97-3.05 (2H, m), 6.92 (1H, s), 7.43 (1H, s).

Provenance & Evidence