Mechanistic Studies of Bismuth(V)-Mediated Thioglycoside Activation Reveal Differential Reactivity of Anomers
DC Field | Value | Language |
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dc.contributor.author | Goswami, M | - |
dc.contributor.author | Ashley, DC | - |
dc.contributor.author | Mu-Hyun Baik | - |
dc.contributor.author | Pohl, NLB | - |
dc.date.available | 2017-01-20T08:32:03Z | - |
dc.date.created | 2016-08-19 | - |
dc.date.issued | 2016-07 | - |
dc.identifier.issn | 0022-3263 | - |
dc.identifier.uri | https://pr.ibs.re.kr/handle/8788114/3290 | - |
dc.description.abstract | The mechanism of bismuth(V)-mediated thioglycoside activation was examined using reaction kinetics and quantum chemical reaction models. NMR experiments show an unusual nonlinear growth/decay curve for the glycosylation reaction. Further studies suggest an anomeric inversion of the beta-glycoside donor to the alpha-donor during its activation, even in the presence of a neighboring 2-position acetate. Interestingly, in situ anomerization was not observed in the activation of an alpha-glycoside donor, and this anomer also showed faster reaction times and higher product diastereoselectivites. Density functional theory calculations identify the structure of the promoter triphenyl bismuth ditriflate, [Ph3Bi(OTf)(2), 1], in solution and map out the energetics of its interactions with the two thioglycoside anomers. These calculations suggest that 1 must bind the thiopropyl arm to induce triflate loss. The computational analyses also show that, unlike most O-glycosides, the beta- and alpha-donor S-glycosides are similar in energy. One energetically reasonable anomerization pathway of the donors is an S(N)1-like mechanism promoted by forming a bismuth-sulfonium adduct with the Lewis acidic Bi(V) for the formation of an oxacarbenium intermediate. Finally, the computed energy compensations needed to form these alpha vs beta Bi adducts is a possible explanation for the differential reactivity of these donors. © 2016 American Chemical Society | - |
dc.description.uri | 1 | - |
dc.language | 영어 | - |
dc.publisher | AMER CHEMICAL SOC | - |
dc.title | Mechanistic Studies of Bismuth(V)-Mediated Thioglycoside Activation Reveal Differential Reactivity of Anomers | - |
dc.type | Article | - |
dc.type.rims | ART | - |
dc.identifier.wosid | 000380181500015 | - |
dc.identifier.scopusid | 2-s2.0-84978485743 | - |
dc.identifier.rimsid | 56244 | - |
dc.date.tcdate | 2018-10-01 | - |
dc.contributor.affiliatedAuthor | Mu-Hyun Baik | - |
dc.identifier.doi | 10.1021/acs.joc.6b00860 | - |
dc.identifier.bibliographicCitation | JOURNAL OF ORGANIC CHEMISTRY, v.81, no.14, pp.5949 - 5962 | - |
dc.citation.title | JOURNAL OF ORGANIC CHEMISTRY | - |
dc.citation.volume | 81 | - |
dc.citation.number | 14 | - |
dc.citation.startPage | 5949 | - |
dc.citation.endPage | 5962 | - |
dc.date.scptcdate | 2018-10-01 | - |
dc.description.wostc | 7 | - |
dc.description.scptc | 7 | - |
dc.description.journalClass | 1 | - |
dc.description.journalRegisteredClass | scie | - |
dc.description.journalRegisteredClass | scopus | - |
dc.subject.keywordPlus | PENTAVALENT ORGANOBISMUTH REAGENTS | - |
dc.subject.keywordPlus | SULFONIUM IONS | - |
dc.subject.keywordPlus | SUGAR SERIES | - |
dc.subject.keywordPlus | CHEMICAL GLYCOSYLATION | - |
dc.subject.keywordPlus | CARBOHYDRATE-CHEMISTRY | - |
dc.subject.keywordPlus | STEREOSELECTIVE GLYCOSYLATIONS | - |
dc.subject.keywordPlus | SELECTIVE OXIDATION | - |
dc.subject.keywordPlus | BISMUTH MOLYBDATES | - |
dc.subject.keywordPlus | OXACARBENIUM IONS | - |
dc.subject.keywordPlus | KINETIC ASPECTS | - |