ISSN:
0009-2940
Keywords:
Ether-phosphines
;
Palladium complexes
;
Fluxional behavior
;
Hydrogenation
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Novel Basic Ligands for the Homogeneous Catalytic Carbonylation of Methanol, XXVIII. - Synthesis, Properties and Fluxional Behavior of (Ether-Phosphine)palladium ComplexesCl2Pd(COD) (1) (COD = 1,5-cyclooctadiene) reacts with 1 equiv, of the (ether-phosphine) ligand Ph2P∼D (2a-c) (D = CH2C4H7O (a), CH2C4H7O2 (b), CH2CH2OCH3 (c)] to give the dimeric complexes [μ-ClPdCl(Ph2P∼D)]2 (3a-c) (P∼D = η1-P-coordinated). According to the field-desorption mass spectra which show only one peak for the monomeric moieties ClPd(Ph2P∼D), 3a-c have a very weak Pd2Cl2 bridge. trans-Cl2Pd(Ph2P∼D)2 (4a-c) is obtained either from 3a-c and 2a-c by cleaving the Pd2Cl2 bridge or from 1 and 2 equiv. of the ligands 2a-c. 4c crystallizes in the monoclinic space group P21/c with Z = 2. AgClO4 selectively abstracts one Cl⊖ ligand from 4a-c which results in the formation of the cationic complexes [trans-(Ph2P∩D)(Ph2P∼D)PdCl]⊕ (5a-c) (P∩D = η2-D,P-coordinated) containing one chelated and one η11-P-bonded (ether-phosphine) ligand. 5a-c show fluxional behavior which is demonstrated by temperature-dependent 31P{1H}-NMR investigations. The coalescence points have been determined and are at 253 (5a), 303 (5b), and 283 K (5c). The activation enthalpies ΔG
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19901231205
