Triethylamine → Methyl 2-hydroxy-4-[3-hydroxy-3-(4,4-dimethylthiochroman-6-yl)-1-propynyl]benzoate

Participants

Reaction Steps

2.5 g (10.8 mmol) of α-ethynyl-4,4-dimethyl-6-thiochromanmethanol, 3 g (10.8 mmol) of methyl 2-hydroxy-4-iodobenzoate and 50 ml of triethylamine were introduced into a three-necked flask. The reaction mixture was degassed with nitrogen for 30 min. and then 600 mg (0.86 mmol) of bis(triphenylphosphine)-palladium(II) chloride and 240 mg (1.3 mmol) of copper iodide were added successively. Stirring was carried out at room temperature for four hours, the reaction mixture was evaporated to dryness and the residue obtained was taken up in water and ethyl ether. The organic phase was separated by settling, dried over magnesium sulfate and evaporated. The residue obtained was purified by chromatography on a silica column eluted with dichloromethane. 3.2 g (80%) of methyl 2-hydroxy-4-[3-hydroxy-3-(4,4-dimethylthiochroman-6-yl)-1-propynyl]benzoate, with a melting point of 105°-106° C., were recovered.

Provenance & Evidence