Palladium overview

Abstract A literature overview, up to the end of 2004, of the most important microwave-assisted transition-metal-mediated processes used for the decoration and construction of heterocycles is presented. The emphasis of the chapter lies in the use of palladium-assisted reactions but examples of copper- and nickel-mediated processes are also incorporated. 

Beilina F, Carpita A, Rossi R (2004) Palladium catalysts for the Suzuki Crosscoupling reaction an overview of recent advances. Synthesis 2419-2440 Bhattacharyya SJ (2000) Polymer-supported reagents and catalysts recent advances in synthetic applications. Comb Chem High Throughput Screening 3 65-92... 

Extensive research in the field led to the publication of several reviews and monographs in the field. The place of our book in this niche is to provide an overview of the developments in the application of palladium, nickel and copper catalyzed transformations in the preparation and functionalization of heterocyclic compounds. Although preference was given to recent results, important examples of earlier (pioneering) works are also included in this monograph. 

The current high level of interest in binuclear metal complexes arises from the expectation that the metal centers in these complexes will exhibit reactivity patterns that differ from the well-established modes of reactivity of mononuclear metal complexes. The diphosphine, bis(diphenylphosphino)methane (dpm), has proved to be a versatile ligand for linking two metals while allowing for considerable flexibility in the distance between the two metal ions involved (1). This chapter presents an overview of the reaction chemistry and structural parameters of some palladium complexes of dpm that display the unique properties found in some binuclear complexes. Palladium complexes of dpm are known for three different oxidation states. Palladium(O) is present in Pd2(dpm)3 (2). Although the structure of this molecule is unknown, it exhibits a single P-31 NMR reso-... 

Over the past 5 years the number of reports on the use of palladium-catalyzed reactions for solid-phase derivatizations has greatly increased. In this section (and throughout this chapter), we limit our scope to representative applications for the modification of solid-supported heterocyclic scaffolds. A more general overview of the versatility of Suzuki, Heck, and Stille reactions on solid supports was recently provided by Franzen.32... 

C-M bond addition, for C-C bond formation, 10, 403-491 iridium additions, 10, 456 nickel additions, 10, 463 niobium additions, 10, 427 osmium additions, 10, 445 palladium additions, 10, 468 rhodium additions, 10, 455 ruthenium additions, 10, 444 Sc and Y additions, 10, 405 tantalum additions, 10, 429 titanium additions, 10, 421 vanadium additions, 10, 426 zirconium additions, 10, 424 Carbon-oxygen bond formation via alkyne hydration, 10, 678 for aryl and alkenyl ethers, 10, 650 via cobalt-mediated propargylic etherification, 10, 665 Cu-mediated, with borons, 9, 219 cycloetherification, 10, 673 etherification, 10, 669, 10, 685 via hydro- and alkylative alkoxylation, 10, 683 via inter- andd intramolecular hydroalkoxylation, 10, 672 via metal vinylidenes, 10, 676 via SnI and S Z processes, 10, 684 via transition metal rc-arene complexes, 10, 685 via transition metal-mediated etherification, overview,... 

Cross-coupling reactions 5-alkenylboron boron compounds, 9, 208 with alkenylpalladium(II) complexes, 8, 280 5-alkylboron boron, 9, 206 in alkyne C-H activations, 10, 157 5-alkynylboron compounds, 9, 212 5-allylboron compounds, 9, 212 allystannanes, 3, 840 for aryl and alkenyl ethers via copper catalysts, 10, 650 via palladium catalysts, 10, 654 5-arylboron boron compounds, 9, 208 with bis(alkoxide)titanium alkyne complexes, 4, 276 carbonyls and imines, 11, 66 in catalytic C-F activation, 1, 737, 1, 748 for C-C bond formation Cadiot-Chodkiewicz reaction, 11, 19 Hiyama reaction, 11, 23 Kumada-Tamao-Corriu reaction, 11, 20 via Migita-Kosugi-Stille reaction, 11, 12 Negishi coupling, 11, 27 overview, 11, 1-37 via Suzuki-Miyaura reaction, 11, 2 terminal alkyne reactions, 11, 15 for C-H activation, 10, 116-117 for C-N bonds via amination, 10, 706 diborons, 9, 167... 

Heterometal alkoxide precursors, for ceramics, 12, 60-61 Heterometal chalcogenides, synthesis, 12, 62 Heterometal cubanes, as metal-organic precursor, 12, 39 Heterometallic alkenes, with platinum, 8, 639 Heterometallic alkynes, with platinum, models, 8, 650 Heterometallic clusters as heterogeneous catalyst precursors, 12, 767 in homogeneous catalysis, 12, 761 with Ni—M and Ni-C cr-bonded complexes, 8, 115 Heterometallic complexes with arene chromium carbonyls, 5, 259 bridged chromium isonitriles, 5, 274 with cyclopentadienyl hydride niobium moieties, 5, 72 with ruthenium—osmium, overview, 6, 1045—1116 with tungsten carbonyls, 5, 702 Heterometallic dimers, palladium complexes, 8, 210 Heterometallic iron-containing compounds cluster compounds, 6, 331 dinuclear compounds, 6, 319 overview, 6, 319-352... 

Metallaboranes, and /-Block metallaboranes, overview, 3,133-174 Metallacarboranes 7-block metal characteristics, 3, 200 deblock metal overview, 3, 175-264 early transition elements, 3, 201 /-block metal characteristics, 3, 246 /-block metal overview, 3, 175-264 late transition elements, 3, 221 linked cage and multi-decker complexes, 3, 245 mid-transition elements, 3, 214 Metallacarbynes, molybdenum, and palladium complexes, 8, 211... 

NLO properties, 12, 771 from oxygenated ligands, 6, 842 with palladium, 8, 213 and Rh Cp complexes, 7, 160 trinuclear clusters, overview, 6, 835-871 Osmium complexes... 

The focus of this review will be on those recent and older contributions to the telomerization field that primarily deal with the palladium-catalyzed telomerization with multifunctional oxygenates. First, a short glossary of commonly used ligands and catalysts is given, followed by a description of the mechanistic intricacies of the process and, finally, the different classes of multifunctional, renewable telogens that are treated in detail. This review complements two other excellent overviews of the telomerization reaction, each with its own primary focus. Behr and co-workers published an extensive review article summarizing the research on telomerization done in the period 1984—2008 with a particular focus on process developments [25]. 

See for example the notebook with publications lists on palladium, ruthenium, and rhodium, ca. 1922, K. U. Leuven Archives, Noddack-Tacke Papers, 63 and the notebook with an overview of the properties of the elements nearby elements 43 and 75,... 

Wacker reactions, which is why we refer to them here [12, 15-17]. Finally, the general concept of a Wacker reaction could be regarded as the palladium-catalyzed oxidative coupling of heteronucleophiles and olefins, and this can obviously be extended to nitrogen nucleophiles and others [18] conversely, the principle of the Cu(I)/Cu(II)/02 reoxidation system for Pd(0) can be applied to other oxidation reactions (for example that of CO to C02), but the present overview is limited to sp2-C-H activation in olefins. 

In comparison to most other methods in surface science, STM offers two important advantages (1) it provides local information on the atomic scale and (2) it does so in situ [50]. As STM operates best on flat surfaces, applications of the technique in catalysis relate to models for catalysts, with the emphasis on metal single crystals. Several reviews have provided excellent overviews of the possibilities [51-54], and many studies of particles on model supports have been reported, such as graphite-supported Pt [55] and Pd [56] model catalysts. In the latter case, Humbert et al. [56] were able to recognize surface facets with (111) structure on palladium particles of 1.5 nm diameter, on an STM image taken in air. The use of ultra-thin oxide films, such as AI2O3 on a NiAl alloy, has enabled STM studies of oxide-supported metal particles to be performed, as reviewed by Freund [57]. 

P-P bonds, 67-68 Palladium catalysis in ionic liquids, overview, 256-257... 

The transition metal catalyzed synthesis of arylamines by the reaction of aryl halides or tri-flates with primary or secondary amines has become a valuable synthetic tool for many applications. This process forms monoalkyl or dialkyl anilines, mixed diarylamines or mixed triarylamines, as well as N-arylimines, carbamates, hydrazones, amides, and tosylamides. The mechanism of the process involves several new organometallic reactions. For example, the C-N bond is formed by reductive elimination of amine, and the metal amido complexes that undergo reductive elimination are formed in the catalytic cycle in some cases by N-H activation. Side products are formed by / -hydrogen elimination from amides, examples of which have recently been observed directly. An overview that covers the development of synthetic methods to form arylamines by this palladium-catalyzed chemistry is presented. In addition to the synthetic information, a description of the pertinent mechanistic data on the overall catalytic cycle, on each elementary reaction that comprises the catalytic cycle, and on competing side reactions is presented. The review covers manuscripts that appeared in press before June 1, 2001. This chapter is based on a review covering the literature up to September 1, 1999. However, roughly one-hundred papers on this topic have appeared since that time, requiring an updated review. 

Abstract N-heterocyclic carbenes (NHCs) have attracted increasing attention since their discovery. Notably, they have allowed for major advances in palladium-catalyzed reactions. Mainly known for their application in cross-coupling reactions, this review intends to provide a broader overview of (NHC)-palladium systems in organic transformations. 

Tsuji J (2002) Overview of the Palladium-Catalyzed Carbon-Carbon Bond Formation via jr-Allylpalladium and Propargylpalladium Intermediates. In Negishi E, de Mei-jere A (eds) Handbook of Organopalladium Chemistry for Organic Synthesis. Wiley, New York, p 1669... 

This review is restricted only to sequences where initial and subsequent steps are catalyzed by palladium complexes. Furthermore, neither Pd-catalyzed unimolecular, parallel, nor multicomponent domino reactions will be treated in this overview. Reactions where identical functionalities are transformed by the same Pd-catalyzed step, i.e., multiple Pd-catalyzed reactions, will also not be covered. Hence, only those processes are within the scope of this review where an initially introduced Pd catalyst or precursor catalyzes related or significantly different reactions and where the sequence offers advantages over the stepwise conducted transformation. With respect... 

Much effort has been devoted to finding synthetically useful methods for the palladium-catalyzed aerobic oxidation of alcohols. For a detailed overview the reader is referred to several excellent reviews [163]. The first synthetically useful system was reported in 1998, when Peterson and Larock showed that simple Pd(OAc)2 in combination with NaHC03 as a base in DMSO as solvent catalyzed the aerobic oxidation of primary and secondary allylic and benzylic alcohols to the corresponding aldehydes and ketones, respectively, in fairly good yields [164, 165]. Recently, it was shown that replacing the non-green DMSO by an ionic liquid (imidazole-type) resulted in a three times higher activity of the Pd-catalyst [166]. 

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