反应详情

Under an argon stream, CH2Cl2 solvent (0.5 ml) was placed in a two-necked flask beforehand, and thereto was added dropwise, at 0 to 5° C., a mixed solution of dimethyl cis-9-octadecenedioate (170 mg, 0.50 mmol) and Bu3N (278 mg, 1.50 mmol) in CH2Cl2 (4.5 ml) over a period of about 1 hour by means of a microfeeder. ZrCl4 (338 mg, 1.45 mmol) was added portionwise every 10 minutes from 5 minutes after the start of dropwise addition of the above mixed solution, 6 times in total. After the completion of the dropwise addition of the mixed solution of the ester and the amine, the whole was further mixed at the same temperature for 15 minutes. Water was added to the reaction mixture and the resulting mixture was stirred and then extracted with ether. The organic layer was washed with water and saturated brine, and then dried over anhydrous sodium sulfate. After the evaporation of the solvent under reduced pressure, the crude product was purified by silica gel chromatography (hexane/ethyl acetate=20/1→10/1) to obtain the aimed product (28 mg, 18%) and a by-product (34-membered ring; 18 mg, 12%).

1. additionbeforehand, and thereto was added dropwise, at 0 to 5° C.
2. additionafter the start of dropwise addition of the above mixed solution, 6 times in total
3. extractionextracted with ether
4. washThe organic layer was washed with water and saturated brine
5. dry with materialdried over anhydrous sodium sulfate
6. customAfter the evaporation of the solvent under reduced pressure
7. customthe crude product was purified by silica gel chromatography (hexane/ethyl acetate=20/1→10/1)