135492-10-3Relevant articles and documents
Novel Basic Ligands for the Homogeneous Catalytic Methanol Carbonylation, XXXI. Cationic Bis(Ether-Phosphine)Metal Complexes of the Nickel Triad with Fluxional Behavior
Lindner, Ekkehard,Dettinger, Johannes
, p. 432 - 439 (2007/10/02)
The (ether-phosphine) ligands R2PCH2C5H9O (1a-c) are obtained from the corresponding alkali metal phosphides MPR2 (M = Li, Na) and 2-chloromethyltetrahydropyran in ether.Reaction of 1a-c with either Cl2M(COD) (COD = 1,5-cyclooctadiene) or Cl2 in a 2:1 ratio leads to the bis(ether-phosphine)metal complexes Cl2M(R2PO)2 trans-2b,c, trans-3b, cis 2a,b, cis-3a, and 4a , in which the ligands 1a-c are η1-P-coordinated.In 2-4 Cl- is abstracted by AgClO4to give the cationic trans-bis(ether-phosphine) complexes O)(R2PO)> (5a, 6a-c, 7a) O = η1-P-coordinated; PO = η2-O,P-coordinated>.In contrast to 7a, the nickel and palladium complexes 5a and 6a-c show fluxional behaviour as demonstrated by temperature dependent 31P NMR spectra.The coalescence temperatures and estimated free energie enthalpies ΔGexcit. of 5a and 6a-c are compared with the corresponding data for the complexes O)(Ph2PO)> (8a-10a) and give an insight into the relative basicity of the ether oxygen atoms.
