Halogen complexes reduction

Iridiuin(iv).—Group VII Donors. All reported studies of Ir concerned halogen complexes. Pure IrF4 has been prepared for the first time via reduction of IrFg on a hot filament of Ir or W. X-Ray powder pattern studies of this volatile, red-brown compound showed it to be different from IrFj or IrFs. A simple melt synthesis of K2lrFg has been developed involving the reaction ... 

Platinum-lead complexes undergo a cleavage of Pt—Pb bond with halogens and halogen acids506,507 510. These reactions are believed to occur through an electrophilic attack on Pt(II) leading to oxidative addition with the formation of a hexa-coordinated Pt(IV) complex. Reductive elimination of a plumbane results in the observed products (equation 193). 

Upon examination of the C-C reductive elimination reaction from a series of halogen complexes (Pd X=C1, Br, I Table 2), a clear trend is observed the heavier the ligand, the smaller the activation barrier, and the larger the exother-micity of the process. Therefore, the easier reductive elimination reaction should be expected from iodide complexes of Pt with the activation energy of only 25.0 kcal/mol and reaction energy of -30.3 kcal/mol. 

Reductive Elimination from Pt" Halogen Complexes [Pt(CH=CH2)2X2l (X=CI, Br, I)... 

A combination of classical and modem synthesis methods allowed chemists to prepare thousands of new stilbenes, which possess a variety of chemical and physical properties, in solution, polymers, and on templates. The synthesized compounds show the rich chemistry involved in multiple reactions such as halogenation, oxidation, reduction, addition, substitution, polymerization, complexation, and so on. 

The heptanuclear iron carbonyl cluster [Fe3(CO)u(/u-H)]2-Fe(DMF)4 (178) acted as an efficient catalyst in the reduction of carboxamides by l,2-bis(dimethylsilyl)benzene in toluene to the corresponding amines in high yields. Several tertiary and secondary amides including a sterically crowded amide were also reduced smoothly A review of the development of optically active cobalt complex catalysts for enan-tioselective synthetic reactions has addressed the applications of ketoiminatocobalt(II) complexes such as (5)-MPAC (179) and (5)-AMAC (180), transition-state models for borohydride reduction, halogen-free reduction by cobalt-carbene complexes. 

Bases function in a more complex way than simply by acting as a halogen acceptor, for they cannot always be used interchangeably, and the product may depend on the base used (58,68,69). Diamines, such as ethylene-, propylene-, or hexamethylene diamines may function differently than monoamines. Diamines were thought to function through chelate formation (32). Loven and Speckamp (40) concluded that selectivity in reduction of a... 

The most important of the tertiary phosphine complexes of platinum(IV) are Pt(QR3)2X4, generally prepared by halogen oxidation [174] of cis- or trans-Pt(QR3)2X2 (Q = P, As, R = alkyl Q = Sb, R = Me), since direct reaction of the platinum(IV) halides with the ligands leads to reduction. Once made, the platinum(IV) compounds are stable to reduction ... 

Transition metal catalysts arc characterized by their redox ehemistry (catalysts can be considered as one electron oxidants/reductants). They may also be categorized by their halogen affinity. While in the initial reports on ATRP (and in most subsequent work) copper266,267 or ruthenium complexes267 were used, a wide range of transition metal complexes have been used as catalysts in ATRP. 

McLafferty rearrangement 133, 163 Meisenheimer complexes 699, 702 Metal-chelated intermediates 838 Metal-halogen exchange 781, 784 Methionine, oxidation of 852-855 Methionine sulphone 853 Methionine sulphoxide 851-869 reduction of 1063 residues of... 

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