217789-76-9Relevant academic research and scientific papers
Palladium (II) complexes of hybrid phosphine - Phosphine oxide ligands
Coyle, Randy J.,Slovokhotov, Yuri L.,Antipin, Mikhail Yu.,Grushin, Vladimir V.
, p. 3059 - 3070 (2008/10/09)
Complexes of the type [L2PdCl2] , where L = Ph2PCH2P (O) Ph2 (dppmO) , Ph2P (CH2) 2P (O) Ph2 (dppeO) , Ph2P (CH2) 3P (O) Ph2 (dpppO) , Ph2P (CH2) 4P (O) Ph2 (dppbO) , and Ph2PC5H4FeC5H4P (O) Ph2 (dppfcO) , were prepared in high yield from Na2 [PdCl4] and 2 equiv. of the corresponding L in dichloromethane-methanol. All complexes, except for [ (dppfcO) 2PdCl2] , can exist as the cis and trans isomers, or mixtures of both, with the cistrans ratio decreasing in media of low polarity. The ferrocene containing complex, [ (dppfcO) 2PdCl2] , appeared to be exclusively trans in both the solid state and solution, as established by single crystal X-ray diffraction of its 1 : 3 benzene solvate. The ion exchange extraction of dichloromethane solutions of [ (dppmO) 2PdCl2] and [ (dppeO) 2PdCl2] with aqueous NaBF4 furnished the corresponding cationic P,O-chelates, cis- [ (dppmO) 2Pd] 2 (BF-4)2 and cis- [ (dppeO) 2Pd] 2 (BF-4)2. Alternatively, these cations can be generated by the reaction between the chloro complexes, [ (dppmO) 2PdCl2] and [ (dppeO) 2PdCl2] , with Ag+. Single crystal X-ray diffraction of cis- [ (dppeO) 2Pd] 2 (BF-4)2 revealed distinct conformations (a puckered chair and a distorted sofa) for the two chelate rings situated around each Pd atom. A polymeric, poorly soluble material, { [ (dpppO) 2Pd] 2 (BF-4)2}n, was isolated from the reaction between [ (dppO) 2PdCl2] and AgNO3 NaBF4, with both coordinated and free phosphoryl groups being present in the product (IR) . In dilute solutions of the { [ (dpppO) 2Pd] 2 (BF-4)2}n, depolymerization occurred, giving rise to the monomeric cationic chelate, cis- [ (dpppO) 2Pd] 2(BF-4)2.
