Toluene → 4-(5-(3-(dimethylamino)prop-1-en-1-yl)thiophen-2-yl)-3-(1-hydroxyethyl)-1H-isochromen-1-one

Participants

Reaction Steps

In a 100 ml 3-necked round bottomed flask (2-(dimethylamino)ethyl)-triphenylphosphonium bromide (1569 mg, 3.79 mmol) was loaded and suspended under Argon in 15 ml of Dioxane. Potassium bis(trimethylsilyl)amide solution 0.5 M in toluene (6.0 ml, 3.03 mmol) was added drop wise and a yellow\orange color appeared. The mixture was further stirred for 20 min then 5-(3-(1-hydroxyethyl)-1-oxo-1H-isochromen-4-yl)thiophene-2-carbaldehyde (Intermediate B37, 455 mg, 1.515 mmol) dissolved in 5 ml of dioxane was added The mixture was further stirred at rt for 2 h then poured into 100 ml of NH4Cl sat. sol. and 200 ml of EtOAc. Phases were separated and the organic one was dried over sodium sulfate. Solvents were removed and the crude was purified by chromatography eluting with DCM\20% MeOH in DCM mixtures to leave 4-(5-(3-(dimethylamino)prop-1-en-1-yl)thiophen-2-yl)-3-(1-hydroxyethyl)-1H-isochromen-1-one (220 mg, 0,619 mmol, 40.9% yield) as a yellow oil.

Provenance & Evidence