| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1322689 | Journal of Organometallic Chemistry | 2013 | 5 Pages |
•Acyl-bridged Pt/Mn complex facilitated the direct desulfurization of thiiranes.•Olefins were produced with complete retention of stereochemistry.•This proceeded via a concerted bimolecular pathway.•Non-bridged complex favors inversion by stepwise desulfurization process.•Control of stereoselectivity appears to be mediated by forced Pt/Mn proximity.
An acyl-bridged heterodinuclear Pt/Mn complex [(dppe)Pt(μ-C(O)Np-1κC,2κO)–Mn(CO)4] (Np = neopentyl, –CH2CMe3) has been prepared and unambiguously characterized. Upon reaction with thiiranes, this species is able to facilitate the direct desulfurization of three-membered S-heterocycles to produce olefins with complete retention of stereochemistry, with kinetic details supporting a concerted mechanism for thiirane desulfurization. Conversion of this species to a non-bridged, opened Pt/Mn complex [(dppe)(NpC(O))Pt–Mn(CO)5] can be effected by reaction with CO(g) in benzene solution. These non-bridged species display the opposite reactivity with thiiranes, generating the isomer with an inverted stereochemistry. Isolation of key thiamanganacyclic intermediates indicate that inversion occurs in the first C–S bond cleavage event, while the second desulfurization step proceeds with retention to produce the olefin. As a result, control of stereoselectivity in this process appears to be mediated by the existence or absence of forced Pt/Mn metal–metal proximity.
Graphical abstractAn acyl-bridged heterodinuclear Pt/Mn complex [(dppe)Pt(μ-C(O)Np-1κC,2κO)–Mn(CO)4] (Np = neopentyl, –CH2CMe3) facilitates the direct desulfurization of three-membered S-heterocycles to produce olefins with complete retention of stereochemistry via a concerted bimolecular desulfurization mechanism, as supported by kinetic experiments.Figure optionsDownload full-size imageDownload as PowerPoint slide
