反应详情

6.64 g (40 mmole) of 3-phenyl-D-lactic acid and 3.7 g (44 mmole) of dihydropyran are reacted in acetonitrile according to the method of Obrecht and Heimgartner [Helv. Chim. Acta 67, 526 (1984)]. The reaction mixture is evaporated at 20-25 millibar from a water bath at about 40° C. The residue is dissolved in 20 ml of dichloromethane, washed with water, dried over sodium sulfate and repeatedly evaporated. The obtained O-tetrahydropyranyl-3-phenyl-D-lactic acid is dissolved in diethyl ether and converted into cyclohexylammonium salt. The crystals are filtered off, washed with diethyl ether and dried at reduced pressure.

1. customThe reaction mixture is evaporated at 20-25 millibar from a water bath at about 40° C
2. dissolutionThe residue is dissolved in 20 ml of dichloromethane
3. washwashed with water
4. dry with materialdried over sodium sulfate
5. customrepeatedly evaporated
6. dissolutionThe obtained O-tetrahydropyranyl-3-phenyl-D-lactic acid is dissolved in diethyl ether
7. filtrationThe crystals are filtered off
8. washwashed with diethyl ether
9. customdried at reduced pressure