反应详情

温度

-78 °C

A 1 M of solution of lithium diisopropylamide in a 3:5 mixture of hexanes/THF (8.25 ml) was added dropwise to (3R,7aS)-3-trichloromethyl-tetrahydro-pyrrolo[1,2-c]oxazol-1-one (1.51 g, prepared as described by Wang and Germanas Synlett 1999, 33-36.) in THF (5 ml) at −78° C. After stirring 30 minutes at −78° C. Eschenmoser's salt (2.78 g) was added. The RM was then allowed to warm to −40° C. with vigorous stirring over 1 h and maintained for 2 h at −40° C. Water was then added and the aqueous layer extracted with DCM, the combined organic layers dried over Na2SO4 and evaporated. The residue was then purified by normal phase chromatography eluting with a gradient from DCM to 20% EtOAc in DCM to give the title compound as a pale yellow oil (M+H=301/303/305 3:3:1).

1. temperatureto warm to −40° C.
2. stirringwith vigorous stirring over 1 h
3. temperaturemaintained for 2 h at −40° C
4. extractionthe aqueous layer extracted with DCM
5. dry with materialthe combined organic layers dried over Na2SO4
6. customevaporated
7. customThe residue was then purified by normal phase chromatography
8. washeluting with a gradient from DCM to 20% EtOAc in DCM