Nicolas reaction

This compound was then allowed to react with COj(CO)g to form the dicobalt-alkyne complex. The Nicolas reaction was then used to form a fused 5,8-ring system. This reaction was followed by an intramolecular PKR to give the polycyclic product in high yield. 

As the cation at the a-position (propargyl position) of acetylene complexes is very stable, the reaction products at the propargyl position with nucleophilic reagents are selectively obtained. Usually, as shown in eq. (17.24), first, the cation is prepared by the reaction of a cobalt complex of propargyl alcohol or propargyl ester with tetrafluoric acid and the nucleophilic reagent reacts with the cation. These reactions are called Nicolas reactions [45,65-67]. 

The Nicolas reaction is that the triple bond coordinates to the cobalt atom, and the triple bond and the carbon atom at the a-position are stabilized. Therefore, with the cobalt compound, the triple bond is stabilized, and the other functional group is able to react. Hence, the cobalt compound is able to be used as the protecting group for a reactive triple bond. For example, the selective reduction of a double bond of a compound having a triple bond and in Friedel-Crafts acylation are shown in eqs. (17.25) and (17.26), respectively [45,68-70]. 

Luminescence reaction of polynoidin. According to Nicolas et al. (1982), purified polynoidin luminesces by the addition of sodium... 

Mertes PM, Moneret-Vautrin DA Skin reactions to intradermal neuromuscular blocking agent injections a randomized multicenter trial in healthy volunteers. Anesthesiology 2007 107 245. Moneret-Vautrin DA, Gueant JL, Kamel L, Laxenaire MC, el Kholty S, Nicolas JP Anaphylaxis to muscle relaxants cross-sensitivity studied by radioimmunoassays compared to intradermal tests in 34 cases. J Allergy Clin Immunol 1988 82 745. 

Other reactions characterized for pyrimidine residues include mercuration at C-5 of cytosine or uracil (Hopman et al., 1986), cycloaddition to the 5,6-double bond of thymine and uracil (Cimino et al., 1985), and thiolation at the C-4 amino group of cytosine (Malcom and Nicolas, 1984). 

Potato LOX has the potential to be used as an alternative model to the mammalian enzyme because of its great availability(Lopez-Nicolas and others 2000). To date, three isoenzymes of potato LOX have been isolated. Several works have reported linoleic acid as the optimum substrate for potato LOX-1, 9-hydroperoxide being the main product of the reaction. Another LOX substrate, linolenic acid, has been reported as the preferred substrate for both potato LOX-2 and -3, which produce 13-hydroperoxide as the main product. 

From the days of the Egyptians, when emeralds were a particular favorite of kings, beryl has also been a favored gemstone. It was not until the late eighteenth century that Abbe Rene Just Haiiy (1743—1822), the father of crystallography, studied the crystalline structures and densities of emeralds and beryl and determined that they were the same mineral. At about the same time, in 1798, Louis-Nicolas Vauquehn (1763—1829) discovered that both emeralds and beryl were composed of a new element with four protons in its nucleus. The element was named glucina because of its sweet taste. It was not until the nineteenth century that the metal berylhum was extracted from berylhum chloride (BeCy by chemical reactions. Late in the nineteenth century, E Lebeau (dates unknown) separated the metal by the electrolytic process. 

The majority of fluorescent probes are water-insoluble and must be dissolved in an organic solvent prior to addition to an aqueous reaction medium containing the DNA to be labeled. Suitable solvents are identified for each fluorophore, but mainly DMF or DMSO are used to prepare a stock solution. Some protocols utilize acetone when labeling DNA. However, avoid the use of DMSO for sulfonyl chloride compounds, as this group reacts with the solvent. For oligonucleotide labeling, the amount of solvent added to the reaction mixture should not exceed more than 20% (although at least one protocol calls for a 50% acetone addition—Nicolas etal., 1992). 

Chevalier, F., Chobert, J.-M., Popineau, Y., Nicolas, M.-G., and Haertle, T. 2001d. Improvement of the functional properties of (3-lactoglobulin glycated through the Maillard reaction is related to the sugar nature, hit. Dairy J. 11, 145-152. 

Peter Englezos and Nicolas Kalogerakis Catalysis of Organic Reactions, edited by Michael E. Ford The Chemical Process Industries Infrastructure Function and Economics, James R. Couper, O. Thomas Beasley, and W. Roy Penney... 

MarziUi, Luigi G., see Toscano, Paul J. Mathey, Francosis, see MezailUes, Nicolas Mayr, Andreas and Bastos, CeciUa M., Coupling Reactions of Terminal Two-Faced p Ligands and Related Cleavage Reaction 40 1... 

In France the supply position was worse. By 1776 the political and financial situation there was making the continuity of the imports of ash to that country (particularly from Spain) doubtful, and a prize was offered by the French Academy of Sciences for a new, commercial process in which soda alkali could be produced from common salt. Duhamel s reactions (mentioned earlier) were, of course, completely uneconomical, but it had been established clearly from such studies in pure chemistry that common salt, sodium sulfate, and sodium carbonate were related through the element sodium, and that a commercial process might, therefore, be achieved. It did not prove easy, however, and it was 1789 before Nicolas Le Blanc devised his process (described later) for making alkali from common salt. He did not base his process on the then-current theory of chemical affinity, which suggested that iron should be used to produce alkali from sodium sulfate because of the great affinity of iron for sulfate (13y 14). Indeed, the theory of the precise chemistry of the Le Blanc process remained obscure until about 100 years later, and Le Blanc well... 

Meyer, T. J., Oxidation-Reduction and Related Reactions of Metal-Metal Bonds Mezaillies, Nicolas, Mathey, Erancois, and Ee Eloch, Pascal, The Coordination Chemistry of Phosphinines Their Polydentate and Macrocyclic Derivatives Michel, Sarah L. J., Hoffman, Brian M., Baum, Sven M., and Barrett, Anthony G. M., Peripherally Functionalized Porphyrazines Novel Metallo-... 

Determination of complex reaction mechanisms analysis of chemical, biological, and genetic networks / John Ross, Igor Schreiber, Marcel O. Vlad widi contributions from Adam Arkin, Peter J. Oefner, and Nicola Zamboni. p. cm. 

Nicolas, J.J. et al. Enzymatic browning reactions in apple and apple products, Crit. Rev. Food Sci., 34, 109, 1994. 

The clinical picture of six adverse reactions associated with the infusion of Lipi-physan prepared from cottonseed oil and soybean lecithin has been extensively described by Nicolas et al. (1966). In two cases the reaction was observed in connection with the first and in one case after the third infusion. These patients had not received Lipiphysan earlier. Two of the patients had tolerated Lipiphysan earher, but renewed infusion 10-15 days later provoked adverse reactions. In the sixth case a continuous series of 17 infusions was well tolerated but the unit 18 provoked a reaction. In this series of patients the symptoms corresponded to those described above chills, flush, headache, episodes of hypo- and hypertension, tachycardia, vomiting, and body temperatures as high as 39.5 °C. All patients recovered from the intolerance reactions. Goulon et al. (1974) have reviewed the clinical data on nine cases of severe late reactions. Eight of these were caused by preparations stabilized with soybean lecithin and one with egg yolk lecithin. 

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