[CH2:1]([CH:4]1[N:7]([Si](C(C)(C)C)(C)C)[C:6](=[O:15])[CH:5]1[CH3:16])[CH:2]=[CH2:3].[F-].[K+].C1OCCOCCOCCOCCOCCOC1>O1CCCC1>[CH2:1]([CH:4]1[NH:7][C:6](=[O:15])[CH:5]1[CH3:16])[CH:2]=[CH2:3]Part of the isomeric mixture from (ii) (1.20 g) in dry tetrahydrofuran (50 ml) was treated with potassium fluoride (0.45 g) and 18-crown-6 ether (0.07 g). After one hour the solution was partitioned between brine and ethylacetate. The organic phase was separated, dried (Na2SO4), evaporated and chromatographed on silica gel 60 (<230 mesh) eluting with ethylacetate:hexane 6:4. This separated the trans and cis isomers of 4-allyl-3-methyl azetidin-2-one.
Wird geladen…