Methyl iodide → HCID 13080739, compound

Participants

Reaction Steps

A solution of (Z)-7-[(1R,2S,3R,5S)-2-(t-butyldimethylsilyloxymethyl)-5-hydroxy-3-(2-tetrahydropyranyloxy)cyclopentyl]-5-heptenoic acid (24) (261 mmol) in acetonitrile (1000 ml) was cooled on ice. Diazabicycloundecene (156.0 ml, 1044 mmol) was added thereto and methyl iodide (65.0 ml, 1044 mmol) was added drop wise to the solution. The reaction mixture was warmed to room temperature, and stirred for 14 hours. The reaction mixture was cooled on ice, diazabicycloundecene (39.0 ml, 261 mmol) and methyl iodide (16.3 ml, 261 mmol) were added, then, the mixture was stirred at room temperature for 1.25 hours. The reaction mixture was again cooled on ice, and diazabicycloundecene (39.0 ml, 261 mmol) and methyl iodide (16.3 ml, 261 mmol) were added. After stirring at room temperature for one hour, the reaction mixture was concentrated under reduced pressure. Ethyl acetate (400 ml) and water (400 ml) were added to the residue and the mixture was stirred, let to stand and then separated into two layers. The aqueous layer was extracted twice with ethyl acetate (400 ml), the organic layers were combined and sequentially washed with 1N-hydrochloric acid (600 ml), saturated sodium bicarbonate water (800 ml) and saturated aqueous sodium chloride (800 ml). After drying with anhydrous magnesium sulfate, the solution was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (Fuji Silysia BW-300: 2000 g; ethyl acetate:hexane=1:3), the fractions containing impurities were re-purified by silica gel column chromatography (Fuji Silysia BW-300: 190 g; ethyl acetate:hexane=1:3) to give methyl (Z)-7-[(1R,2S,3R,5S)-2-(t-butyldimethylsilyloxymethyl)-5-hydroxy-3-(2-tetrahydropyranyloxy)cyclopentyl]-5-heptenate (25) (110.4 g, 233.5 mmol, 89.5%) as colorless oil.

Provenance & Evidence