p-Toluenesulfonic acid → HCID 66998464, compound

Participants

Reaction Steps

A mixture of 7-fluoro-2-hydroxy-2,3-dihydro-benzofuran-4-carboxylic acid ethyl ester and 7-fluoro-2-methoxy-2,3-dihydro-benzofuran-4-carboxylic acid ethyl ester (1.15 g, see above) in toluene (6.0 mL) is added dropwise to a solution of PTSA (0.25 mmol) in toluene (5.0 mL) which is heated to reflux. Heating is continued for 5 h, an additional portion of PTSA (0.25 mmol) is added and the mixture is again heated to reflux for 7 h. The solvents are removed in vacuo and the residue is purified by FC (gradient: heptane to heptane/EtOAc 95/5) to give the desired product.

Provenance & Evidence