Carbon-X bonds

Hydrolysis is one of a family of reactions which leads to the transformation of pollutants. Under environmental conditions, hydrolysis occurs mainly with organic compounds. Hydrolysis is a chemical transformation process in which an organic RX reacts with water, forming a new molecule. This process normally involves the formation of a new carbon-oxygen bond and the clearing of the carbon-X bond in the original molecule ... 

Infrared and Raman Studies of -Complexes, 1, 239 Insertion Reactions of Compounds of Metals and Metalloids, 5, 225 Insertion Reactions of Transition Mfetal-Carbon Bonded Compounds. I. Carbon Monoxide Insertion, 11, 87... 

The transition state represents the hiehest ener [y structure involved in this step of the reaction. It ts unstable and con t be isolated, but we can nevertheless imagine it to be an activated complex of the two reactants in which the carbon carbon, x bond is partially broken uiid the now carbon-hydrogen bond is partially formed (Figure 5-.6). 

Considering then the series a, b, and d in Table 7 the substitution of one hetero-atom lowers the barrier or has little effect which fits with the monosubstitution effect. The series 19 can be extended to 19e X=dimethyl-silyl 79/, X = selenium and 19g, X = tellurium.72) For 19e the barrier to inversion in 5.4 kcal/mol 3) and for 79/ and 19g, it appears to be much lower than in cyclohexane, or in 19a to 19d, since no changes are seen in the nmr spectrum at —100°. It may be in these cases the low barrier reflects the unusual flatness of the six-membered ring, and perhaps particular ease of rotation about carbon-X bonds, both of which may be consequences of these bonds being relatively long. 4)... 

Cyclometallation is a reaction in which a chelate metal alkyl or aryl is generated by cleavage of a C—H bond in a coordinated ligand, a new metal-carbon [Pg.388]

Elimination reactions which give rise to multiple bonds between carbon and a heteroatom occur with particular facility and show many of the characteristics of olefin-forming processes. Most often one of the eliminating fragments is a hydrogen atom, which is easily removed from a heteroatom and the choice of mechanism, between an anion or a concerted process, will depend on the lability of the beta carbon-X bond, e.g. 

Table III. Carbon-X Bond Dissociation Enthalpies as a Function of the Electronegativity of X...

The carbonylative palladium-catalyzed reactions discussed in this section proceed by oxidative addition of palladium (0) to the carbon-X bond of aryl/vinyl/acyl halides and pseudohalides followed by carbon monoxide insertion, giving rise to an acylpalla-dium intermediate. The acylpalladium intermediate can in turn react with various tethered nucleophiles (a), be involved in activation/hetero or carbopalladation steps with unsaturated carbon-carbon bonds (b), or participate in cascade reactions (c) (Scheme 13.1). 

Carbon-oxygen and carbon-halogen bonds are polar covalent bonds and carbon bears a partial positive charge in alcohols ( " C—0 ) and in alkyl halides ( " C—X ) Alcohols and alkyl halides are polar molecules The dipole moments of methanol and chloromethane are very similar to each other and to water... 

Acetylene is linear and alkynes have a linear geometry of their X—C=C—Y units The carbon-carbon triple bond m alkynes is com posed of a CT and two tt components The triply bonded carbons are sp hybridized The ct component of the triple bond contains two electrons m an orbital generated by the overlap of sp hybndized orbitals on adja cent carbons Each of these carbons also has two 2p orbitals which over lap m parrs so as to give two tt orbitals each of which contains two electrons... 

Aryl halides are compounds of the type Ar—X where X = F Cl Br or I The carbon-halogen bond is stronger m ArX than m an alkyl halide (RX)... 

Structural parameters and interatomic distances derived from electron diffraction (7) (77JST(42)l2i) and X-ray diffraction (8) studies (76AX(B)3178) provide unequivocal evidence that pyrazine is planar with >2a symmetry. There is an increased localization of electron density in the carbon-nitrogen bonds, with carbon-carbon bonds being similar in length to those in benzene. ... 

Huang, T J Dong, Z X, Shreeve, J M Inorg Chem 1987,26, 2604 Denson, D D, Uyemo, E T, Simon, R L, Peters, H M In Biochemistry Involving Carbon-Fluorine Bonds, Filler, R, Ed, ACS Symposium Se Ties 8, American Chemical Society Washington, DC, 1976 p 190 Van DerPuy, M 7 Fluorine Chem 1979,13 375 Shustov, L D, Nikolenko, L N, Senchenkova, T M Zh Obshch Khim 1983, 5i m.Chern Abstr 1983, 9S 143326v... 

Compounds that have the same number of carbon atoms can be compared by adding the number of C-O, C-N, and C-X bonds in each and then subtracting the number of C—H bonds. The larger the resultant value, the higher the oxidation level. 

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