299196-85-3Relevant academic research and scientific papers
Oxazolium-derived azomethine ylides. External oxazole activation and internal dipole trapping in the synthesis of an aziridinomitosene
Vedejs, Edwin,Piotrowski, David W.,Tucci, Fabio C.
, p. 5498 - 5505 (2007/10/03)
Intermolecular alkylation of the aziridinyl oxazole 20 using PhSO2CH2CH2OTf is possible despite the presence of potentially nucleophilic aziridine nitrogen. The resulting oxazolium salt 22 reacts with BnNMe3(+)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-induced cleavage 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 aziridine ester 16 can be prepared by the aza-Darzens reaction of 15 with tert-butyl chloroacetate.
