Potassium Iodide → HCID 67605616, compound

Participants

Reaction Steps

A mixture of intermediate (6) (2.3 g), 4-chloro-1-(3,4,5-trimethoxyphenyl)-1-butanone (2 g), sodium carbonate (2.1 g) and potassium iodide (catalytic quantity) in 4-methyl-2-pentanone (150 ml; previously dried over MgSO4) was stirred and refluxed overnight. The reaction mixture was cooled, washed with water, dried over MgSO4, filtered and the filtrate was evaporated. The residue was purified by column chromatography over silica gel (eluent: CH2Cl2, upgrading to CH2Cl2 /(CH3OH/NH3) 97/3). The pure fractions were collected and the solvent was evaporated. The residue was dissolved in methanol and converted into the ethanedioic acid salt with ethanedioic acid (0.6 g). The mixture was boiled, then cooled and the precipitate was filtered off and recrystallized from 2-propanol. The precipitate was dissolved in aqueous NH4OH/CH2Cl2. The organic layer was separated, dried over MgSO4, filtered and the solvent was evaporated. The residue was stirred in boiling diisopropylether, cooled and the resulting precipitate was filtered off and dried (vacuum; 80° C.), yielding 1.10 g of (±)-cis-3-methoxy-1-[4-oxo-4-(3,4,5-trimethoxyphenyl)butyl]-4-piperidinyl 4-amino-5-chloro-2,3-dihydro-7-benzofurancarboxylate (28%); mp. 132.3° C. (compound 1). In a similar manner there were also prepared:

Provenance & Evidence