Carbon derivatives

Ailyl enol carbonates derived from ketones and aldehydes undergo Pd-cat-alyzed decarboxylation-elimination, and are used for the preparation of a, /3-unsaturated ketones and aldehydes. The reaction is regiospecific. The regio-isomenc enol carbonates 724 and 726, prepared from 723, are converted into two isomeric enones, 725 and 727. selectively. The saturated aldehyde 728 can be converted into the a,/3-unsaturated aldehyde 730 via the enol carbonate 729[459]. 

In addition to alcohols, some other nucleophiles such as amines and carbon nucleophiles can be used to trap the acylpalladium intermediates. The o-viny-lidene-/j-lactam 30 is prepared by the carbonylation of the 4-benzylamino-2-alkynyl methyl carbonate derivative 29[16]. The reaction proceeds using TMPP, a cyclic phosphite, as a ligand. When the amino group is protected as the p-toluenesulfonamide, the reaction proceeds in the presence of potassium carbonate, and the f>-alkynyl-/J-lactam 31 is obtained by the isomerization of the allenyl (vinylidene) group to the less strained alkyne. 

Whiting at one time coimoted only a very fine form of chalk of micrometer sizes but the term is now used more broadly to include all finely divided, meticulously milled carbonates derived from high calcium or dolomitic limestone, marble, shell, or chemically precipitated calcium carbonate. Unlike all of the above natural forms of limestone, it is strictly a manufactured product. 

Analysis. Dilute aqueous solutions of hydroxyhydroquiaone turn blue-green temporarily when mixed with ferric chloride. The solutions darken upon addition of small amounts, and turn red with additions of larger amounts of sodium carbonate. Derivatives used for identification are the picrate, which forms orange-red needles (mp of 96°C), and the triacetate (mp 96—97°C). Thin-layer chromatography and Hquid chromatography are well suited for the quahtative and quantitative estimation of hydroxyhydroquiaone (93,94). 

Just as the alkanes and alkenes had general formulas, the carbon derivatives all have general formulas. The hydrocarbon backbone provides a portion of the general formula, and the functional group provides the other part. In each case, the hydrocarbon derivative is represented by the formula R-, and the hydrocarbon backbone has its own specific formula. The term substituted hydrocarbon is another name for hydrocarbon derivative, because the functional group is substituted for one or more hydrogen atoms in the chemical reaction. 

G. Reactions with Carbon Dioxide and Some Carbonic Derivatives.. ... 

In this review an attempt is made to discuss all the important interactions of highly reactive divalent carbon derivatives (carbenes, methylenes) and heterocyclic compounds and the accompanying molecular rearrangements. The most widely studied reactions have been those of dihalocarbenes, particularly dichlorocarbene, and the a-ketocarbenes obtained by photolytic or copper-catalyzed decomposition of diazo compounds such as diazoacetic ester or diazoacetone. The reactions of diazomethane with heterocyclic compounds have already been reviewed in this series. ... 

Continuous curve.- f(F) = F (The weighting fimction implying total routing collagen carbon derives only from diet protein). 

For consistency in designating the relative configuration the carbonyl group is numbered (1). The newly formed bond is labeled 2,3- and successive carbons are numbered accordingly. The carbons derived from the enolate are numbered 2, 3, etc., starting with the cr -carbon. 

Finally, a weak jt-type halogen bonding involving a cyclopentadienyl ring and the iodine atom of an iodofluorocarbon [89] is a rare example of a Tt-bonded io do carbon derivative, in contrast to numerous examples of halogen bonding of the latter with n-type electron donors [2,20]. 

Scheme I Synthesis of succinimidyl carbonate derivatives of polyethylene glycol.

Kato S, Niyomura O (2005) Group 1-17 Element (Except Carbon) Derivatives of Thio-, Seleno- and Telluro-Carboxylic Acids. 251 19-85 Kato S, see Niyomura O (2005) 251 1-12... 

C3 plants Plants as, for example, cotton and wheat, in which, during the photosynthesis process, a stable compound consisting of three bonded carbon atoms is first formed during the fixation of carbon derived from carbon dioxide in the plants over 95% of the plant species on the earth are C3 plants see C4 and CAM plants. 

Holbrook RD, Love NG, Novak JT (2004) Sorption of 17-beta-estradiol and 17 alpha-ethinylestradiol by colloidal organic carbon derived from biological wastewater treatment systems. Environ Sci Technol 38 3322-3329... 

Fig. 3 Examples of monomer units having reactive side-chain groups, which can be copolymerized with polyesters (a) a-malic acid, (b) [S-malic acid, (c) a-carboxyl- -caprolactone, (d) carboxy lactic acid, (e) trimethylene carbonate derivative, and (1) depsipeptide...

Figure 14.16 DSC can be used to activate hydroxyl-particles to a reactive NHS-carbonate derivative. The subsequent coupling of amine-containing ligands can be done in either organic solvent or aqueous conditions.

The biosphere is an important reservoir of carbon, derived from atmospheric carbon dioxide, which it both obtains from the... 

Deacylation of hydrophobic p-nitrophenyl alkanoates Hydroxamic acid and phenyl ester derivatives had alkyl or fluoroalkyl substituents. Rate effects depend on selectivity of binding of fluoro- and hydro-carbon derivatives Kunitake et ai, 1984... 

C SOC retained SOClost SOC sSOC SOC SOC n Associated 813C value Amount of organic carbon lost Rayleigh fractionation constant of the SOC Soil organic carbon derived from com stover Total corn-derived carbon in the residue returned treatment Com derived from unharvested material in the stover harvested treatment... 

This section focuses on the heavier element group 14 terphenyl compounds. However, some carbon derivatives that have obvious synthetic importance are also described briefly. 

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