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dc.contributor.authorKarodia, Nazira*
dc.contributor.authorAitken, R.A.*
dc.contributor.authorMassil, T.*
dc.contributor.authorYoung, R.J.*
dc.date.accessioned2009-08-17T10:31:47Z
dc.date.available2009-08-17T10:31:47Z
dc.date.issued2002
dc.identifier.citationR.A. Aitken, R.A., Karodia, N., Massil, T. and Young, R.J. (2002). Flash vacuum pyrolysis of stabilised phosphorus ylides: Part 17. Preparation of aliphatic amino acid derived y-alkoxycarbonyl-amino-B-oxo ylides and pyrolysis to give a,B-acetylenic y-amino acid and GABA analogues. Journal of the Chemical Society, Perkin Transactions 1: Organic and Biomolecular Chemistry. Vol. 2002, No. 4, pp. 533-541.en
dc.identifier.urihttp://hdl.handle.net/10454/3312
dc.descriptionNoen
dc.description.abstractA series of eleven alpha-aminoacyl stabilised phosphorus ylides 9-19 have been prepared by condensation of N-alkoxycarbonyl protected amino acids with Ph3P=CHCO2Et using a carbodiimide peptide coupling reagent. Upon ash vacuum pyrolysis at 600 degreesC, these undergo extrusion of Ph3PO to give the corresponding, alpha,beta-acetylenic gamma-amino esters 21-29, 33 and 34 in moderate yield. In two cases the terminal alkynes 30 and 31 are also formed. The beta-aminoacyl ylide 20 from beta-alanine similarly gives the alpha,beta-acetylenic delta-amino ester 35 upon pyrolysis. Regioselective addition of HBr to the triple bond of one acetylenic ester 25 was observed giving a mixture of E and Z alpha-bromoacrylates 36. Hydrogenation of the N-Cbz acetylenic esters 21-23 and 33 results in N-deprotection and hydrogenation of the triple bond to afford the chiral GABA analogues 37-40 in 70 --> 95% ee as determined by F-19 NMR of their Mosher amides. Fully assigned C-13 NMR spectra of all the ylides and acetylenic ester derivatives are presented.en
dc.language.isoenen
dc.relation.isreferencedbyhttp://dx.doi.org/10.1039/b110243een
dc.subjectStereospecific synthesisen
dc.subjectDerivativesen
dc.subjectMechanismen
dc.subjectFacileen
dc.titleFlash vacuum pyrolysis of stabilised phosphorus ylides. Part 17. Preparation of aliphatic amino acid derived gamma-alkoxycarbonyl-amino-beta-oxo ylides and pyrolysis to give alpha,beta-acetylenic gamma-amino acid and GABA analoguesen
dc.status.refereedYesen
dc.typeArticleen
dc.type.versionNo full-text available in the repositoryen


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