Ammonia → 1-(4-fluorophenyl)-1,3-dihydro-1-[3-(tetrahydro-2H-pyran-2-yloxy)propyl]isobenzofuran

Beteiligte Stoffe

Reaktionsschritte

To a stirred and cooled (2-propanone/CO2 -bath) amount of 1080 parts of ammonia was added 1 part of iron (III)chloride, followed by the portionwise addition of 7.7 parts of sodium under nitrogen atmosphere. After stirring for 20 minutes, there was added dropwise a solution of 64.5 parts of 1-(4-fluorophenyl)-1,3-dihydroisobenzofuran in 105 parts of 1,1'-oxybisethane while still cooling. Then there was added dropwise a solution of 75 parts of 2-(3-bromopropoxy)tetrahydro-2H-pyran in 37 parts of 1,1-oxybisethane. Upon completion, stirring was continued for 2 hours under nitrogen atmosphere in a 2-propanone/CO2 -bath. Without cooling and without nitrogen, there were added dropwise slowly 490 parts of 1,1'-oxybisethane and stirring was continued overnight at room temperature. 225 Parts of a saturate ammonium chloride solution were added dropwise followed by the addition of 200 parts of water. The layers were separated and the aqueous phase was extracted twice with 1,1'-oxybisethane. The combined organic phases were washed with water, dried, filtered and evaporated. The residue was purified by column-chromatography over silica gel using a mixture of trichloromethane and methanol (99.5:0.5 by volume) as eluent. The second fraction was collected and the eluent was evaporated, yielding 39.6 parts of 1-(4-fluorophenyl)-1,3-dihydro-1-[3-(tetrahydro-2H-pyran-2-yloxy)propyl]isobenzofuran as a residue (intermediate 10).

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