反应详情

To 8.5 g of 7-bromoheptanoic acid t-butyl ester (prepared as described in Reference Example 1) in 80 ml of methylene chloride was added dropwise 18.2 ml of a 25% solution of diisobutyl alminium hydride in toluene at -78° C. over a period of 1 hours. The solution was stirred at the same temperature, to which was added 5 ml of methanol at from 0° C. to 10° C. and then added 10 ml of water, and the mixture was stirred at 30° C. to 40° C. for 1 hour. The deposited crystals were filtered out, and the filtrate was concentrated under reduced pressure. The residue was purified by column chromatography on silica gel using a mixture of methylene and chloride and cyclohexane (1:1) as an eluent to give 5.28 g of the title compound having the following physical characteristic:

1. stirringthe mixture was stirred at 30° C. to 40° C. for 1 hour
2. filtrationThe deposited crystals were filtered out
3. concentrationthe filtrate was concentrated under reduced pressure
4. customThe residue was purified by column chromatography on silica gel using
5. additiona mixture of methylene and chloride and cyclohexane (1:1) as an eluent