Barium complexes with crown-ether-functionalised amidinate and iminoanilide ligands for the hydrophosphination of vinylarenes

Abstract : The detailed multistep syntheses of two nitrogen-based sterically congested iminoanilidine and amidine proligands bearing a tethered 15-member aza-ether-crown macrocycle, namely {I^Acrown}H and {Amcrown}H, are reported. These proligands react with [Ba{N(SiMe2H)2}2·(thf)n] to generate the heteroleptic barium complexes [{I^Acrown}BaN(SiMe2H)2] (5) and [{Amcrown}BaN(SiMe2H)2] (6) in high yields. These complexes exhibit high coordination numbers (resp. eight and seven) and are in addition stabilised by mild BaH-Si interactions. Unusually for oxophilic elements such as barium, the amidinate ligand in 6 is only η1-coordinated. Complexes 5 and 6 mediate the intermolecular hydrophosphination of styrene with primary (PhPH2) and secondary (HPPh2) phosphines. Their catalytic performance compares favourably with those of other barium precatalysts for these reactions. During the course of the hydrophosphination of styrene with HPPh2 catalysed by 5, the phosphide complex [{I^Acrown}BaPPh2] (7) could be intercepted and crystallographically characterised.
Document type :
Journal articles
Complete list of metadatas

Cited literature [42 references]  Display  Hide  Download

https://hal-univ-rennes1.archives-ouvertes.fr/hal-02150460
Contributor : Laurent Jonchère <>
Submitted on : Monday, July 8, 2019 - 2:30:59 PM
Last modification on : Wednesday, July 10, 2019 - 1:17:01 AM

File

Le Coz-2019-Barium complexes w...
Files produced by the author(s)

Identifiers

Citation

Erwann Le Coz, Hanieh Roueindeji, Thierry Roisnel, Vincent Dorcet, Jean-François Carpentier, et al.. Barium complexes with crown-ether-functionalised amidinate and iminoanilide ligands for the hydrophosphination of vinylarenes. Dalton Transactions, Royal Society of Chemistry, 2019, 48 (25), pp.9173-9180. ⟨10.1039/c9dt01512d⟩. ⟨hal-02150460⟩

Share

Metrics

Record views

25

Files downloads

12