Author, as appears in the article.: Ricart, J. M. ; García-López, D.; Civit, M.; Vogels, C. ; Westcott, S. ; Fernández, E. ; Carbó, J.
Department: Química Física i Inorgànica
URV's Author/s: RICART PLA, JOSE MANUEL; García-López, D.; Civit, M.; Vogels, C. ; Westcott, S. ; FERNÁNDEZ GUTIÉRREZ, MARIA ELENA; CARBÓ MARTIN, JORGE JUAN
Keywords: selenoboration stereoselective anti-addition
Abstract: The stereoselective anti-addition of selenoboranes to α,β-acetylenic esters and amides was achieved in a transition metal-free context using catalytic amounts of PCy3. The reaction provides anti-3,4- selenoboration with concomitant delivery of α-vinyl selenides by protodeboronation with MeOH. Interestingly, in the absence of phosphine the selenoboration switches towards the formation of β-vinyl selenides. Theoretical calculations rationalize the regio- and stereoselectivity of the reaction by discovering a new mechanism for the anti-3,4-selenoboration. While the selenoborane is activated via the “push–pull” effect of B, the phosphine interacts with the β position of the alkynoate switching the polarity of the triple bond and favoring 1,3-selenoboration which provides the α-addition of the selenyl group. Then, the autocatalytic action of a second selenoborane reagent, which coordinates to the phosphorus ylide intermediate, determines the stereoselectivity and completes the catalytic process. Finally, the comparison of selenoborane reagents with diboranes and silaboranes, which have exhibited analogous reactivity, shows that the selenium moiety has a larger nucleophilic character favoring the performance of the reaction under mild conditions.
Research group: Química Quàntica
Thematic Areas: Química Química Chemistry
licence for use: https://creativecommons.org/licenses/by/3.0/es/
ISSN: 2044-4753
Author identifier: 0000-0002-2610-5535; ; ; ; ; 0000-0001-9025-1791; 0000-0002-3945-6721
Record's date: 2019-01-25
Last page: 3628
Journal volume: 8
Papper version: info:eu-repo/semantics/publishedVersion
Link to the original source: https://pubs.rsc.org/en/content/articlelanding/2018/CY/C7CY02295F#!divAbstract
Funding program: plan; Excelencia; CTQ2016-80328-P plan; Excelencia; CTQ2014-52774-P altres; Grupos consolidados; 2014SGR199
Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
Article's DOI: 10.1039/c7cy02295f
Entity: Universitat Rovira i Virgili
Journal publication year: 2018
First page: 3617
Publication Type: Article Artículo Article