Triphenylphosphine → 5-(1-Isopropyl-piperidin-4-yloxy)-benzo[b]thiophene-2-carboxylic acid methyl ester

Participants

Reaction Steps

The above prepared 5-hydroxy-benzo[b]thiophene-2-carboxylic acid methyl ester (0.143 g, 0.687 mmol) was dissolved in 3.4 mL of THF and treated successively at 10° C. with 1-isopropyl-piperidin-4-ol (0.197 g, 2 eq.), triphenylphosphine (0.360 g, 2 eq.) and DIAD (0.267 mL, 2 eq.), and the mixture then kept at ambient temperature for another 2 h. Pouring onto crashed ice, twofold extraction with AcOEt, washing with water, drying over sodium sulfate, and evaporation of the solvents, followed by flash chromatography (SiO2, NEt3/AcOEt=5/95), delivered 0.222 g of the title compound as light yellow oil.

Provenance & Evidence