Author, as appears in the article.: Pubill-Ulldemolins, Cristina; Fernanez, Elena; Bo, Carles; Brown, John M.;
Department: Química Física i Inorgànica
URV's Author/s: Bo Jané, Carles / Fernández Gutiérrez, Maria Elena
Abstract: In 1954 Schlesinger and co-workers observed the direct reaction of diboron tetrachloride with simple organic compounds under mild conditions, the 1,2 addition product being formed with either ethylene or acetylene. In the following 25 years a series of addition reactions to simple alkenes, alkynes and dienes was demonstrated. B2F4 was shown to react in similar manner, albeit under more forcing conditions. Crucially, it was demonstrated that the addition to (E)- or (Z)-but-2-ene occurred with cis-stereospecificity. Only sporadic interest was shown in this field thereafter until catalysed addition reactions of diboron reagents were realized. Encouraged by this revival of interest through the discovery of transition-metal and nucleophilic catalysis of diboryl additions, DFT analysis of uncatalysed additions of B2X4 has been carried out and interpreted. This includes the relative reactivity of several B-B reagents with ethene, and that of B2Cl4 vs. B2F4 additions, including benzene, naphthalene and C60 as reactants. This allows the analysis of relative reactivity vis-à-vis substitution on boron, and also direct comparison with hydroboration by HBCl2. [4 + 2] Addition of diboron reagents to dienes with B-B cleavage competes with direct [2 + 2] addition, favourably so for B2F4. The computational results demonstrate that the stereospecific addition to isomeric but-2-enes is a rare concerted [2σs + 2πs] process.
Thematic Areas: Química Physical and theoretical chemistry Organic chemistry Odontología Medicina ii Medicina i Materiais Interdisciplinar General medicine Farmacia Ciências biológicas iii Ciências biológicas ii Ciências biológicas i Ciências agrárias i Chemistry, organic Biotecnología Biodiversidade Biochemistry
licence for use: https://creativecommons.org/licenses/by/3.0/es/
Author's mail: carles.bo@urv.cat mariaelena.fernandez@urv.cat
Author identifier: 0000-0001-9581-2922 0000-0001-9025-1791
Record's date: 2024-09-07
Papper version: info:eu-repo/semantics/publishedVersion
Link to the original source: https://pubs.rsc.org/en/content/articlelanding/2015/ob/c5ob01280e
Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
Papper original source: Organic & Biomolecular Chemistry. 13 (37): 9619-9628
APA: Pubill-Ulldemolins, Cristina; Fernanez, Elena; Bo, Carles; Brown, John M.; (2015). Origins of observed reactivity and specificity in the addition of B<sub>2</sub>Cl4 and analogues to unsaturated compounds. Organic & Biomolecular Chemistry, 13(37), 9619-9628. DOI: 10.1039/c5ob01280e
Article's DOI: 10.1039/c5ob01280e
Entity: Universitat Rovira i Virgili
Journal publication year: 2015
Publication Type: Journal Publications
Repositori URV