Oxygen carboxylate

Figure 2.57. Symmetry- and atom-resolved XES spectra of deprotonated glycine on Cu(110) displaying clockwise from the left oxygen, carboxylic carbon, methyl carbon, and nitrogen -shell XES spectra with from top to bottom the pz, p, and px spectrum contributions. From Ref. [3].

An infrared study of the interaction of ethane with a Pd/Al203 catalyst did not reveal any absorption bands of adsorbed species at (seemingly) 373 K but strong bands indicative of oxygenated (carboxylate) surface species were obtained at temperatures between 373 and 478 K when ethane plus air was in contact with the catalyst (733). 

Potassiumltert-butanol-oxygen Carboxylic acids by oxidative desulfuration... 

M ercuryj nitrogen d i oxi d e I oxygen Preferential replacement of halogen by oxygen Carboxylic acid fluorides from polyhalides... 

Barteauwas able to demonstrate for well-defined Ti02 and ZnO surfaces the activity and selectivity for C2 oxygenate (carboxylates and aldehydes) and hydrocarbon (alkynes) coupling reactions over these model metal oxide surfaces under UHV conditions that is typically only seen in organometallic systems in solution. 

Trialky loxonium fluoroborate Replacement of sulfur by oxygen Carboxylic acid amides from thioamides... 

Amino acid analyses of a variety of hemocyanins indicate that a large amount of histidine and methionine per copper pair is present as well as cysteine, although the number involved in disulfide bridges has not been determined. Intuitively, three types of donor atoms are likely to be involved in these protein complexes, namely, oxygen (carboxylate, phenolate, and water), nitrogen (amine, amide anion, and imidazole), and sulfur (thioether and thiolate). Furthermore, copper (II) can adopt square-planar, square-pyramidal, trigonal-bipyramidal, octahedral, and tetrahedral geometries. 

Osmium tetroxide N-methylmorpholine oxide peroxide a-Hydroxyketones from ethylene derivatives s. lA, 222 s. a. J. Org. Ghem. 2A, 1517 (1959) Platinum oxygen Carboxylic acids from alcohols s. 15, 261 C CH C(OH)CO Pt/0 CH2OH COOH... 

Supplement 1952 2666-3031 Carbonyl compounds Ethylene carbonate, 100. Piperonal, 116. Thioindigo, 177. Fluorescein, 222. Carboxylic acids Piperonylic acid, 269. Amines, 328. Three Cyclic Oxygens, 381. Four Cyclic Oxygens, 433. Fiite Cyclic Oxygens, 459.. . . ... 

These are effective high-octane gasoline additive oxygenates. The conversion of isobutane into isopropyl, methyl ketone, or isopentane into isobutyl, methyl ketone is illustrative. In this reaction, no branched carboxylic acids (Koch products) are formed. 

In order for the transferability of parameters to be a good description of the molecule, force fields use atom types. This means that a sp carbon will be described by different parameters than a. sp - carbon, and so on. Usually, atoms in aromatic rings are treated differently from sp atoms. Some force fields even parameterize atoms for specific functional groups. For example, the carbonyl oxygen in a carboxylic acid may be described by different parameters than the carbonyl oxygen in a ketone. 

Cyclopentene derivatives with carboxylic acid side-chains can be stereoselectively hydroxy-lated by the iodolactonization procedure (E.J. Corey, 1969, 1970). To the trisubstituted cyclopentene described on p. 210 a large iodine cation is added stereoselectively to the less hindered -side of the 9,10 double bond. Lactone formation occurs on the intermediate iod-onium ion specifically at C-9ot. Later the iodine is reductively removed with tri-n-butyltin hydride. The cyclopentane ring now bears all oxygen and carbon substituents in the right stereochemistry, and the carbon chains can be built starting from the C-8 and C-12 substit""" ... 

Carboxylate ion (RC—O ) An ester IS formed when the negatively charged oxygen of a carboxylate re places the halogen of an alkyl halide... 

The next several chapters deal with the chemistry of various oxygen containing func tional groups The interplay of these important classes of compounds—alcohols ethers aldehydes ketones carboxylic acids and derivatives of carboxylic acids— IS fundamental to organic chemistry and biochemistry... 

The acyl group of the carboxylic acid acyl chloride or acid anhydride is trans ferred to the oxygen of the alcohol This fact is most clearly evident m the esterification of chiral alcohols where because none of the bonds to the chirality center is broken m the process retention of configuration is observed... 

The reaction of alcohols with acyl chlorides is analogous to their reaction with p toluenesulfonyl chloride described earlier (Section 8 14 and Table 15 2) In those reactions a p toluene sulfonate ester was formed by displacement of chloride from the sulfonyl group by the oxygen of the alcohol Carboxylic esters arise by displacement of chlonde from a carbonyl group by the alcohol oxygen... 

The structural features of the carboxyl group are most apparent m formic acid Formic acid IS planar with one of its carbon-oxygen bonds shorter than the other and with bond angles at carbon close to 120°... 

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