Palladium complexes syntheses

Uson, R., Fomies, J., Laguna, A. and Valenzuela, J.I. (1982) Pseudohalo-bridged pentafiuorophenyl gold-palladium complexes. Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 12(7), 935-946. 

Sasaki Y, Inoue Y, Hashimoto H (1976) Reaction of carbon dioxide with butadiene catalysed by palladium complexes. Synthesis of 2-ethylidenehept-5-en-4-olide. J Chem Soc, Chem Commun 605-606... 

Synthesis. The most common staiting materials for palladium complexes are PdCl2 [7647-10-1] and [PdClJ [14349-67-8]. Commercially available materials useful for laboratory-scale synthesis iuclude [Pd2(OOCCH2)J [3375-31-3] [PdCl2(NCCgH )] [14220-64-5] [Pd(acac)2] [14024-61-4] [PdCl2(cod)] [12107-56-1], and [Pd(P(CgH5)3)J [14221-01-3]. 

Seven procedures descnbe preparation of important synthesis intermediates A two-step procedure gives 2-(HYDROXYMETHYL)ALLYLTRIMETH-YLSILANE, a versatile bifunctional reagent As the acetate, it can be converted to a tnmethylenemethane-palladium complex (in situ) which undergoes [3 -(- 2] annulation reactions with electron-deficient alkenes A preparation of halide-free METHYLLITHIUM is included because the presence of lithium halide in the reagent sometimes complicates the analysis and use of methyllithium Commercial samples invariably contain a full molar equivalent of bromide or iodide AZLLENE IS a fundamental compound in organic chemistry, the preparation... 

The original Sonogashira reaction uses copper(l) iodide as a co-catalyst, which converts the alkyne in situ into a copper acetylide. In a subsequent transmeta-lation reaction, the copper is replaced by the palladium complex. The reaction mechanism, with respect to the catalytic cycle, largely corresponds to the Heck reaction.Besides the usual aryl and vinyl halides, i.e. bromides and iodides, trifluoromethanesulfonates (triflates) may be employed. The Sonogashira reaction is well-suited for the synthesis of unsymmetrical bis-2xy ethynes, e.g. 23, which can be prepared as outlined in the following scheme, in a one-pot reaction by applying the so-called sila-Sonogashira reaction ... 

Palladium, polymethylenebis(diphenylphosphine)-bis(thiocyanato)-linkage isomers, 1, 185 Palladium, tetraammine-tetrachloropalladate history, 1, 2 Palladium, tetrachloro-crystal structure, 1, 16 Palladium, tris(dinitrogen)-synthesis, 1,28 Palladium complexes a,(5-dione dioximates electrical properties, 6, 143 acetylacetone hydrolysis, 2,379 alkylperoxo... 

The systematic synthesis and spectral examination of a large series of complexes, M(ol)n, ra = 1-3, M = Ni or Pd, has been performed (140 -142), with special reference to the optical spectra of the products, again affirming the usefulness of the technique for observing spectral trends as a function of substituent (see later). A number of interesting points emerged from this study, some of which have already been alluded to. The optical data for the nickel and palladium complexes respectively are reported in Tables XVI and XVII. 

The reaction of the stabilized yUde 46 (a-vinyl substituted) with the cycloocta-dienyl Pd(II) allows the synthesis of a novel complex, the (rj -allyl)palladium 47, in which the olefmic double bond participates in the coordination (Scheme 20) [83]. The coordination of the bis-yUde 48 with the same starting Cl2Pd(COD) leads to the formation of another new palladium complex 49 via COD exchange reactions. A C-coordination mode takes place between the carbanionic centers of the bis-ylide and the soft palladium and two stereogenic centers of the same configuration are thus created [83]. In contrast to the example described in Scheme 19, the Cl2M(COD) (M=Pd or Pt), in presence of a slightly different car-... 

Reinhoudt and coworkers studied the synthesis of hyper-branched polymers composed of organopalladium complexes with an SCS pincer ligand [11]. Removal of acetonitrile ligands on palladium led to the self-assembly of dinu-clear palladium complex (9) to give hyper-branched polymer (10), which was... 

Hydrosilylation of dienes accompanied by cyclization is emerging as a potential route to the synthesis of functionalized carbocycles. However, the utility of cycliza-tion/hydrosilylation has been Umited because of the absence of an asymmetric protocol. One example of asymmetric cycUzation/hydrosilylation has been reported very recently using a chiral pyridine-oxazoUne ligand instead of 1,10-phenanthroline of the cationic palladium complex (53) [60]. As shown in Scheme 3-21, the pyridine-oxazoUne Ugand is more effective than the bisoxazoUne ligand in this asymmetric cyclization/hydrosilylation of a 1,6-diene. 

The synthesis, structure, and catalytic properties of a Pd11 complex with a partially hydrogenated ligand, shown in Figure 31, are described.393 This study provides the first asymmetric epoxidation of alkenes catalyzed by a palladium complex.393... 

Dubois et al. [184] reported the synthesis of phosphorus based dendrimers terminated with multivalent palladium complexes. Iterative free radical addition... 

Asymmetric synthesis of tricyclic nitro ergoline synthon (up to 70% ee) is accomplished by intramolecular cyclization of nitro compound Pd(0)-catalyzed complexes with classical C2 symmetry diphosphanes.94 Palladium complexes of 4,5-dihydrooxazoles are better chiral ligands to promote asymmetric allylic alkylation than classical catalysts. For example, allylic substitution with nitromethane gives enantioselectivity exceeding 99% ee (Eq. 5.62).95 Phosphi-noxazolines can induce very high enatioselectivity in other transition metal-catalyzed reactions.96 Diastereo- and enantioselective allylation of substituted nitroalkanes has also been reported.9513... 

In a more recent study, Wang and coworkers have discussed microwave-assisted Suzuki couplings employing a reusable polymer-supported palladium complex [141]. The supported catalyst was prepared from commercial Merrifield polystyrene resin under ultrasound Bonification. In a typical procedure for biaryl synthesis, 1 mmol of the requisite aryl bromide together with 1.1 equivalents of the phenyl-boronic acid, 2.5 equivalents of potassium carbonate, and 10 mg of the polystyrene-... 

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