Aryl complexes chemistry

Alkene complexes Ammine complexes Aqueous chemistry Arsine complexes Binary compounds Bipyridyl complexes Bond lengths acetylacetonate alkene complexes alkyl and aryl complexes ammine complexes aqua ion... 

The products of oxidative addition of acyl chlorides and alkyl halides to various tertiary phosphine complexes of rhodium(I) and iridium(I) are discussed. Features of interest include (1) an equilibrium between a five-coordinate acetylrhodium(III) cation and its six-coordinate methyl(carbonyl) isomer which is established at an intermediate rate on the NMR time scale at room temperature, and (2) a solvent-dependent secondary- to normal-alkyl-group isomerization in octahedral al-kyliridium(III) complexes. The chemistry of monomeric, tertiary phosphine-stabilized hydroxoplatinum(II) complexes is reviewed, with emphasis on their conversion into hydrido -alkyl or -aryl complexes. Evidence for an electronic cis-PtP bond-weakening influence is presented. 

The efficiency of functionalized cyclopentadienyl complexes is meanwhile well established [78,191-202]. Because cyclopentadienyl ligands still dominate the field of organolanthanide chemistry, a selection of the functionalized ligands utilized is depicted in Fig. 11. In the field of aryl complexes, which represented the first well-characterized homoleptic derivatives [203], multiple functionalization has already been started [204]. 

The latter is outside the scope of organometallic chemistry, but within the first two topics the work involved three main themes olefin and acetylene complexes, alkyl and aryl complexes, and hydride complexes. As continuous subsidiary themes throughout ran the complex chemistry of tertiary phosphines and such ligands, the nature of the trans effect, and the nature of the coordinate bond. All the work from 1947 to 1969 was carried out in the Butterwick Research Laboratories, later renamed Akers Research Laboratories, of Imperial Chemical Industries Ltd., and I am indebted to that Company and particularly to Mr. R. M. Winter, the Company s Controller of Research, and Sir Wallace Akers, its Director of Research, who in 1947, made available to me the opportunity to develop my research in my own way, in those laboratories. 

Over the years the homoleptic see Homoleptic Compound) alkyl and aryl complexes were one of the major challenges in organolanthanide chemistry. The simplest organometallic... 

Pyridine complexes can show analogous hindered rotation to that observed with metal-aryl complexes. This has been observed for over SOyears, but recent interest in supramolecular chemistry, particularly by Fujita and Stang, wherein bipyridyls have been used as linkers has spurred renewed interest in the phenomenon. Several articles on dynamics provide leading references for applications of EXSY and other DNMR methods in these systems. BINAP complexes with picolines and methyl-substituted isoquinolines, which show syn and anti isomerism, have been investigated, for example, (48), (49), and (50). ... 

A more prevalent reaction is the arylation of various organic substituents for which an extensive and complex chemistry has been established. Thus C- and O-arylations of phenols and enols are known as well as some S- and N-arylations. Some of these reactions can be facilitated by addition of a catalytic amount of a copper salt. 

When stripped to its naked minimum, the thermal chemistry of aryl azides is deceptively simple. Excluding those compounds bearing reactive ortho substituents [3] and reactions carried out in the presence of active olefins [4], the thermolysis of an aryl azide simply causes unimolecular loss of nitrogen. The complexity arises in subsequent steps where intervention of the various intermediates shown in Figure 1 has been postulated to precede formation of isolatable products. The photolysis of aryl azides is further complicated by the inclusion of reactions originating from electronically excited singlet and triplet states of the azide itself [5]. In essence, a clear understanding of aryl azide chemistry requires the description of the participation and role of each of these reactive intermediates under various reaction conditions. 

Intramolecular versions and domino reactions involving appropriately functionalized aryl halides and alkynes offer useful synthetic methods for a variety of heterocycles and carbocycles. Few other methods can compete with these Pd-catalyzed cyclizations in versatility. Numerous reports and a number of excellent reviews covering the carbo- and heteroannulations have been pubhshed [10]. In order to aid understanding of this somewhat complex chemistry, the cyclizations are classified in to three types (Scheme 3.8). 

A-Arylhydrazones are useful agricultural materials. Moreover, they can be cleaved to form A-arylhydrazines for pyrazole synthesis, and the hydrazine portion can be transferred to ketones to serve as substrates for the Fischer indole synthesis.t The reactions of benzophenone hydrazone with aryl halides have been reported, and to date these reactions are best conducted with chelating phosphine ligands such as DPPF and BINAP, as shown in Eq. 22. These catalyst systans have been the only ones reported for hydra-zone arylation. The chemistry of hydrazonato complexes is similar to that of aniUdes and diarylamides.f Thus, the reactions of aryl chlorides with hydrazones should be accessible in the future using alkylphosphine ligands. 

Our group has explored in detail the reactivity of 82 and the dicyclohexylphos-phino analog 84 (Scheme 6.19). These Pt chloride complexes were utiHzed as precursors for the synthesis of Pt alkyl complexes and cations of the type [(PSiP)Pt]", with the goal of accessing highly reactive metal complexes that would engage in E-H bond activation chemistry [77]. Indeed, square planar Pt alkyl and aryl complexes of the type (R -PSiP)PtR (85, R = Ph, R = CH2Ph 86,... 

Scheme 4 Oxidation chemistry of trans- and cw-Pt (t -alkynyl)(aryl) complexes DDQ =...

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