Transition Metal and Organic

Transition Metal and Organic Redox-Active Macrocycles Designed to Electrochemically Recognize Charged and Neutral Guest Species Paul D. Beer... 

New anions of the general formula [Ta(CO)sL]z prepared by this method included [Ta(CO)5(AsPh3)]" and [Ta(CO)5(CN)]2 (54). The cyanide derivative is of particular interest because its synthesis suggests that other more interesting dianionic species, such as [Ta(CO)5(C=CR)]2 and related [Ta(CO)5(f/1-hydrocarbyl)]2 species, might be accessible materials. Clearly, much chemistry of [Nb(CO)5]3 and [Ta(CO)5]3 remains to be explored. Of particular interest will be a systematic examination of the reactions of these materials with transition metal and organic electrophiles. 

TRANSITION METAL AND ORGANIC REDOX-ACTIVE MACROCYCLES DESIGNED TO ELECTROCHEMICALLY RECOGNIZE CHARGED AND NEUTRAL GUEST SPECIES... 

This section highlights some of the significant features of chromium(O) carbonyls and of the chemistry of this oxidation state. Further information can be found in the articles Carbonyl Complexes of the Transition Metals and Organic Synthesis using Transition Metal Carbonyl Complexes, and in the review literature. ... 

Coordinate covalent bonds involve the unequal sharing of an electron pair by two atoms, with both electrons (originally) coming from the same atom. The electron pair donor is the ligand, or Lewis base, whereas the acceptor is the central atom (because it frequently can accept more than one pair of electrons), or Lewis acid. These bonds are important in all interactions between transition metals and organic ligands (e.g., Fe + in hemoglobin and the cytochromes). 

Here we show that the rectangular molecular boxes composed of transition metals and organic ligands are predictably and quantitatively catenated if the boxes involve parallel aromatic rings with an interplanar separation of 3.5 A. 

N-HeterocycUc carbenes in transition metal and organic catalysis 06AR(B)168. 

Non-cross-linked polymers soluble in acetone or butanone can be produced from Fe (or other transition metals) and organic acids under the influence of aldehydes ... 

BRIDGING TRANSITION METAL AND ORGANIC MOLECULES BONDING CAPABILITIES OF FRAGMENTS OF TRANSITION METAL COMPLEXES... 

Inorganic cations such as sodium, potassium, ammonium, calcium, magnesium, heavy and transition metals, and organic amines are present in foods and their concentrations can significantly vary. 

In gas chromatography, thermotropic hquid crystals belonging to such groups of chemical compounds as Schiff s base, azo- and azoxy-compounds, esters, derivatives of biphenyls and terphenyls, organic complexes with transition metals, and organic polymers are used. Siloxane polymers of liquid-crystaUine properties are stable within the wide range of temperatures from 50°C to 300°C. 

Figure 1.14. An isolobal analogy of transition metal and organic fragments.

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