p-Toluenesulfonic acid → HCID 18694189, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of intermediate 16-b (0.036 mol), 2,5-dimethoxytetrahydrofuran (0.22 mol) and PTSA (catalytic quantity) in DMF (140 ml) was stirred for 90 min at 100° C. The solvent was evaporated. The residue was dissolved in CH2Cl2. The organic solution was washed once with water, dried (MgSO4), filtered and the solvent was evaporated. The residue was purified by column chromatography over silica gel (eluent: CH2Cl2). The pure fractions were collected and the solvent was evaporated, yielding 6.6 g (55.3%) of (±)-6-fluoro-3,4-dihydro-8-(1H-pyrrol-1-yl)-2-[[(tetrahydro-2H-pyran-2-yl)oxy]-methyl]-2H-1-benzopyran (interm. 17-b).

Provenance & Evidence