Oxazolium-Derived Azomethine Ylides. External Oxazole Activation and Internal Dipole Trapping in the Synthesis of an Aziridinomitosene
作者:Edwin Vedejs、David W. Piotrowski、Fabio C. Tucci
DOI:10.1021/jo0001277
日期:2000.9.1
BnNMe(3)(+)CN(-) to produce the azomethine ylide 24b via electrocyclic ring opening of an oxazoline 23b. Internal cycloaddition affords 26 in 66% yield. After saponification and base-inducedcleavage of the N-phenylsulfonylethyl group, conventional cyclization provides access to 33. Deprotection and DDQ oxidation completes the synthesis of the aziridinomitosene derivative 9b. The starting cis-disubstituted