反应详情

温度

0 °C

Tetrahydrofuran [1040 ml, 3 ml/g with respect to the compound of formula (8)] was added to the compound of formula (8) prepared in Example 1 on the premise that the yield of Example 1 is 100%, and the mixture was cooled to 0° C. Titanium tetraisopropoxide (113.8 g, 0.4 mol) was added thereto, and ethyl magnesium bromide (1500 ml, 3.0 mol, 1 M concentration) was added thereto dropwise at 5˜15° C. over 3˜6 hours. After completion of the reaction was confirmed by HPLC, 20% aqueous citric acid solution [1790 ml, 5 ml/g with respect to the compound of formula (8)] was added to the reaction solution under the condition of not exceeding 35° C., which was stirred for about 1 hour. After the stirring, tetrahydrofuran therein was distilled under reduced pressure, and the residue was extracted twice, first with 1390 ml [4 ml/g with respect to the compound of formula (8)] of ethyl acetate and second with 690 ml [2 ml/g with respect to the compound of formula (8)] of the same. Thus resulted organic layer was washed with saturated aqueous NaHCO3 solution [690 ml, 2 ml/g with respect to the compound of formula (8)], and concentrated under reduced pressure to give the title compound of formula (9).

1. waitdropwise at 5˜15° C. over 3˜6 hours
2. additionwas added to the reaction solution under the condition of not
3. customexceeding 35° C.
4. distillationAfter the stirring, tetrahydrofuran therein was distilled under reduced pressure
5. extractionthe residue was extracted twice, first with 1390 ml [4 ml/g with respect to the compound of formula (8)] of ethyl acetate
6. washThus resulted organic layer was washed with saturated aqueous NaHCO3 solution [690 ml, 2 ml/g with respect to the compound of formula (8)], and
7. concentrationconcentrated under reduced pressure