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dc.contributor.authorAitken, R. Alan
dc.contributor.authorBoubalouta, Youcef
dc.contributor.authorChang, Da
dc.contributor.authorCleghorn, Lee P.
dc.contributor.authorGray, Ian P.
dc.contributor.authorKarodia, Nazira
dc.contributor.authorReid, Euan J.
dc.contributor.authorSlawin, Alexandra M.Z.
dc.date.accessioned2017-11-01T14:25:48Z
dc.date.available2017-11-01T14:25:48Z
dc.date.issued2017-09-18
dc.identifier.citationAitken, RA., Boubalouta, Y., Chang, D., Cleghorn, LP., Gray, IP., Karodia, N., Reid, EJ and Slawin, AMZ. (2017) 'The value of 2 J P–CO as a diagnostic parameter for the structure and thermal reactivity of carbonyl-stabilised phosphonium ylides' Tetrahedron, 73 (44) pp. 6275-6285 doi: https://doi.org/10.1016/j.tet.2017.09.016
dc.identifier.issn0040-4020
dc.identifier.doi10.1016/j.tet.2017.09.016
dc.identifier.urihttp://hdl.handle.net/2436/620819
dc.description.abstractA survey of 20 carbonyl-stabilised phosphonium ylides with recently reported X-ray structures shows a strong correlation between the CP to CO torsion angle and the value of 2JP–CO, with high values being associated with an anti configuration and low with syn. Seven new X-ray structural determinations are reported, several for types of ylide not crystallographically characterised before, and these also conform to this pattern. The value of 2JP–CO is then correlated with whether or not thermal extrusion of Ph3PO occurs to give alkynes for over 200 ylides and an empirical rule developed that the extrusion never occurs for ylides where this value is > 11 Hz. This is used to rationalise the anomalous behaviour of some trioxo ylides and cyclic ylides, two of which afford cycloalkynes, isolated after rearrangement as the isomeric 1,3-dienes. The rule also holds for a family of novel highly fluorinated ylides which afford fluorinated alkynes in good yield upon flash vacuum pyrolysis.
dc.description.sponsorshipEPSRC (U.K.) for a DTA Studentship (Grant No. EP/P505712/1)
dc.language.isoen
dc.publisherElsevier
dc.relation.urlhttp://linkinghub.elsevier.com/retrieve/pii/S0040402017309389
dc.subjectYlides
dc.subjectX-ray structure
dc.subjectNMR coupling constants
dc.subjectPyrolysis
dc.subjectCycloalkynes
dc.titleThe value of 2 J P–CO as a diagnostic parameter for the structure and thermal reactivity of carbonyl-stabilised phosphonium ylides
dc.typeJournal article
dc.identifier.journalTetrahedron
dc.date.accepted2017-09-11
rioxxterms.funderUniversity of Wolverhampton
rioxxterms.identifier.projectUoW011117NK
rioxxterms.versionAM
rioxxterms.licenseref.urihttps://creativecommons.org/CC BY-NC-ND 4.0
rioxxterms.licenseref.startdate2018-09-18
dc.source.volume73
dc.source.issue44
dc.source.beginpage6275
dc.source.endpage6285
refterms.dateFCD2018-10-19T09:24:44Z
refterms.versionFCDAM
refterms.dateFOA2018-11-02T00:00:00Z
html.description.abstractA survey of 20 carbonyl-stabilised phosphonium ylides with recently reported X-ray structures shows a strong correlation between the CP to CO torsion angle and the value of 2JP–CO, with high values being associated with an anti configuration and low with syn. Seven new X-ray structural determinations are reported, several for types of ylide not crystallographically characterised before, and these also conform to this pattern. The value of 2JP–CO is then correlated with whether or not thermal extrusion of Ph3PO occurs to give alkynes for over 200 ylides and an empirical rule developed that the extrusion never occurs for ylides where this value is > 11 Hz. This is used to rationalise the anomalous behaviour of some trioxo ylides and cyclic ylides, two of which afford cycloalkynes, isolated after rearrangement as the isomeric 1,3-dienes. The rule also holds for a family of novel highly fluorinated ylides which afford fluorinated alkynes in good yield upon flash vacuum pyrolysis.


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