Complexes of the tripodal phosphine ligands PhSi(XPPh$_2$)$_3$ (X = CH$_2$, O): synthesis, structure and catalytic activity in the hydroboration of CO$_2$ - CEA - Commissariat à l’énergie atomique et aux énergies alternatives Accéder directement au contenu
Article Dans Une Revue Dalton Transactions Année : 2016

Complexes of the tripodal phosphine ligands PhSi(XPPh$_2$)$_3$ (X = CH$_2$, O): synthesis, structure and catalytic activity in the hydroboration of CO$_2$

Résumé

The coordination chemistry of Fe$^{2+}$, Co$^{2+}$ and Cu$^+$ ions was explored with the triphosphine and triphosphinite ligands PhSi{CH$_2$PPh$_2$}$_3$ (1) and PhSi{OPPh$_2$}$_3$ (2), so as to evaluate the impact of the electronic properties of the tripodal phosphorus ligands on the structure and reactivity of the corresponding complexes. The synthesis and characterization of the complexes [Fe(κ$^3$-PhSi{CH$_2$PPh$_2$}$_3$)(MeCN)$_3$][OTf]$_2$ (3) (OTf = O$_3$SCF$_3$), [Fe(κ$^3$-PhSi{OPPh$_2$}$_3$)(MeCN)$_3$][OTf]$_2$ (3’), [Co(κ$^2$-PhSi{CH$_2$PPh$_2$}$_3$)Cl$_2$] (4), [Co(κ$^3$ -PhSi {OPPh$_2$}$_3$)Cl$_2$] (4’), [Cu(κ$^3$-PhSi{CH$_2$PPh$_2$}$_3$)Br] (5) and [Cu(κ$^3$-PhSi{OPPh$_2$}$_3$)I] (5’) were carried out. The crystal structures of 3, 3’, 4, 4’, and of the solvates 5·3THF and 5’·THF are reported. Complexes 3–5’ were shown to promote the catalytic hydroboration of CO$_2$ with (9-BBN)$_2$ (9-BBN = 9-borabicyclo [3.3.1]nonane). While the iron and cobalt complexes of the triphosphine 1 are more active than the analogous complexes with 2, the opposite trend is observed with the copper catalysts. Overall, the copper catalysts 5 and 5’ are both more reactive and more selective than the Fe and Co catalysts, enabling the formation of the acetal H$_2$C(OBBN)$_2$ with a high molar ratio of H$_2$ C(OBBN)$_2$:CH$_3$OBBN up to 92 : 8.

Domaines

Matériaux
Fichier principal
Vignette du fichier
preprint C6DT02135B.pdf (2.26 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

cea-01369401 , version 1 (15-02-2019)

Identifiants

Citer

Alicia Aloisi, Jean-Claude Berthet, Caroline Genre, Pierre Thuéry, Thibault Cantat. Complexes of the tripodal phosphine ligands PhSi(XPPh$_2$)$_3$ (X = CH$_2$, O): synthesis, structure and catalytic activity in the hydroboration of CO$_2$. Dalton Transactions, 2016, 45, pp.14774-14788. ⟨10.1039/c6dt02135b⟩. ⟨cea-01369401⟩
63 Consultations
202 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More