Carbon monoxide derivatives

Iron, as found in the porphyrin derivative hemoglobin, complexes CO to form a stable metal carbonyl. Iron also forms a variety of metal carbon monoxide derivatives such as the homoleptic Fe(CO)5, Fe2(CO)9 and Fe3(CO)i2, the anionic [Fe(CO)4] and its covalent derivative Fe(CO)4Br2, [CpFe(CO)2] and its alkylated covalent derivatives CpFe(CO)2-R with its readily distinguished n (and and a (and / ) iron carbon bonds. By contrast. Mg in its chlorin derivative chlorophyll, which very much resembles porphyrin, forms no such bonds with CO nor is there a rich magnesium carbonyl chemistry (if indeed, there is any at all). 

The use of RuC13 also causes decomposition of the solvent. With such a metal, however, the product of the reaction is H2(OMP) [24]. The carbon monoxide derived from the decomposition of the solvent is added to the macrocycle in a ring expansion reaction generating the porphyrin ring. 

A.2.1 Chemical Exergy of Hydrogen and Carbon Monoxide Derived Using Eugacity-Based Equilibrium Constants... 

Oxanickelacyclopentenones (87) react in many different ways. With carbon monoxide, derivatives of 94 are formed.Insertion of an alkyne leads to the ring-expanded seven-membered oxanickelacycloheptadienones 96, which on hydrolysis yield oxacyclopentenones (99) or dienes (98). Reductive elimination of the organic substrate from 96 is also observed to give... 

ORD measurements in the Soret region of the carbon monoxide derivative of cytochrome oxidase showed a single Cotton effect near 430 nm, which indicated that only cytochrome a3 has an optically active transition, while the non-reacting cytochrome a subunit did not show measurable optical activity (249). By comparison of oxidation-reduction... 

Upon reaction of allene with one equivalent of ozone, trisection occurs to provide carbon monoxide derived from the central carbon atom and carbonyl compounds from the remaining carhon atoms. In the example of eq 31, allene ozonolysis is used to prepare a versatile protected a-hydroxyaldehyde. ... 

The Cl excess line width in the presence of the two trout hemoglobins was studied as a function of sodium chloride concentration. No significant difference between the deoxy and carbon monoxide derivatives was observed for Hb-Trout IV in the range 0.3 to 0.8 M NaCl. 

Both isocyanide and carbon monoxide derivatives have proved to be valuable precursors of a wide range of compounds including hydrido (vide supra) and aryl or alkyl complexes (see Chapter 6.15). Compounds [MCl2(CNR)( -arene)] (M = Os, arene = l,3,5-C6H3Me3, R = Cy, 2,6-xylyl M = Ru, arene = l,2,4,5-C6H2Me4,... 

It may be noticed that the spectrum of the carbon monoxide derivative (curve IV) is very similar to that of the oxygen derivative (curve II). For films with more than 90% of polystyrene, the ferrohemochrome-like spectrum becomes more diffuse. These films oxygenate and deoxygenate more slowly and may also be kept in contact with air-saturated water for days without being oxidized to the Fe(III)-state. 

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