69861-71-8Relevant articles and documents
Capturing a ghost. synthesis and structural characterization of Pd(dba)[P(o -Tol)3]2
Harding, Brennen A.,Melvin, Patrick R.,Dougherty, William,Kassel, Scott,Goodson, Felix E.
, p. 3570 - 3573 (2013)
In an effort to improve upon a literature synthesis of bis[tris(o-tolyl) phosphine]palladium(0) (1) from tris(o-tolyl)phosphine and Pd 2(dba)3, we instead isolated a new compound which proved to have the composition Pd(dba)[P(o-Tol)3]2 (2), upon analysis by X-ray crystallography. While this is not the first known palladium compound containing both dba and phosphine ligands, it is, to our knowledge, the first containing dba and tris(o-tolyl)phosphine. This is significant, because mixtures of Pd2(dba)3 and tris(o-tolyl)phosphine are routinely used in cross-coupling protocols, and palladium complexes containing dba and tris(o-tolyl)phosphine have been cited as intermediates in organometallic and polymerization reactions. The most interesting crystallographic parameter for 2 is an abnormally long Pd-P bond length of 2.388(1) A, which we believe is the cause of this complex's metastability. We also present an alternative synthesis of 1 that does not require a large excess of phosphine.
Stoichiometric and Catalytic Aryl-Perfluoroalkyl Coupling at Tri-tert-butylphosphine Palladium(II) Complexes
Ferguson, Devin M.,Bour, James R.,Canty, Allan J.,Kampf, Jeff W.,Sanford, Melanie S.
supporting information, p. 11662 - 11665 (2017/09/07)
This Communication describes studies of Ph-RF (RF = CF3 or CF2CF3) coupling at Pd complexes of general structure (PtBu3)PdII(Ph)(RF). The CF3 analogue participates in fast Ph-CF3 coupling (II complex. Furthermore, they show that this undesired pathway can be circumvented by changing from a CF3 to a CF2CF3 ligand. Ultimately, the insights gained from stoichiometric studies enabled the identification of Pd(PtBu3)2 as a catalyst for the Pd-catalyzed cross-coupling of aryl bromides with TMSCF2CF3 to afford pentafluoroethylated arenes.
1,6-Diene complexes of palladium(0) and platinum(0): Highly reactive sources for the naked metals and [L-M0] fragments
Krause, Jochen,Cestaric, Günter,Haack, Karl-Josef,Seevogel, Klaus,Storm, Werner,P?rschke, Klaus-Richard
, p. 9807 - 9823 (2007/10/03)
The complexes (cod)MCl2 (M = Pd, Pt; cod = cis,cis-1,5-cyclooctadiene) react with Li2(cot) (cot = cyclooctatetraene) in a 1,6-diene/diethyl ether mixture (1,6-diene = hepta-1,6-diene, diallyl ether, dvds (1,3-divinyl- 1,1,3,3-tetramethyldisiloxane)) to afford the isolated homoleptic dinuclear Pd0 and Pt0 compounds Pd2(C7H12)3 (1), Pd2(C6H10O)3·C6H10O (2'; 2: Pd2(C6H10O)3), Pd2(dvds)3 (3), and Pt2(C7H12)3 (4). When 1-4 are treated with additional 1,6-diene the equally homoleptic but mononuclear derivatives of type M(1,6-diene)2 (5-8) and with ethene the mixed alkene complexes (C2H4)M(1,6-diene) (9-12) are obtained in solution. Complexes 1-12 react with donor ligands such as phosphanes, phosphites, or (t)BuNC to give isolated complexes of types L-M(1,6-diene) (13-41), which have also been prepared by other routes. In all complexes the metal centers are TP-3 coordinated: complexes 1-4 contain chelating and bridging 1,6-diene ligands, whereas the other complexes contain a chelating 1,6-diene ligand and an η2-alkene (5-12) or η1-donor ligand (13-41). Of the studied 1,6-diene complexes the hepta-1,6-diene derivatives are most reactive, while the diallyl ether complexes are often more convenient to handle. The readily isolable dinuclear hepta-1,6-diene and diallyl ether complexes 1, 2', and 4, and their mononuclear pure olefin derivatives are among the most reactive sources for naked Pd0 and Pt0. The corresponding L-M(1,6-diene) complexes are equally reactive precursor compounds for the generation of [L-M0] fragments in solution, which for M =Pd are available otherwise only with difficulty. The results are significant for the operation of naked Pd0 and L-Pd0 catalysts in homogeneous catalysis.
