Bond of alkyl halides

The carbon-halogen bonds of aryl halides are both shorter and stronger than the carbon-halogen bonds of alkyl halides In this respect as well as m their chemical behavior they resemble vinyl halides more than alkyl halides A hybridization effect seems to be responsible because as the data m Table 23 1 indicate similar patterns are seen for both carbon-hydrogen bonds and carbon-halogen bonds An increase m s... 

The carbon-halogen bond of alkyl halides is polarized. 

Since halogen atoms are more electronegative than carbon, the carbon-halogen bond of alkyl halide is polarised the carbon atom bears a partial positive charge whereas the halogen atom bears a partial negative charge. 

The polarity of carbon-halogen bond of alkyl halides is responsible for their nucleophilic substitution, elimination and their reaction with metal atoms to form organometallic compounds. Nucleophilic substitution reactions are categorised into and on the basis of their kinetic properties. Chirality has a profound role in understanding the reaction mechanisms of Sj l and Sj 2 reactions. Sj 2 reactions of chiral all l halides are characterised by the inversion of configuration while Sj l reactions are characterised by racemisation. 

The insertion reactions of 16 into the C-Hal bond of alkyl halides were found to be the most convenient model for CIDNP studies. Since in accordance with Scheme 10 the photolysis of 17 leads to the formation of triplet germylene 16, we start with the first evidence of the reactions of triplet excited 1676. 

Alkylindium diiodides or dibromides can be prepared in high yield by the insertion of the In(I) halide into the C—X bond of alkyl halides ... 

Polarization of antibonding orbitals explains the regiochemistry of intermolecular nucleophilic reactions, such as the generally observed attack at carbon atom in C-X bond of alkyl halides and C=O bonds of carbonyls (Figure 5.6). 

The C-X bond of alkyl halides and sulfonate esters is polarized such that the carbon has a positive dipole. Halides and sulfonate anions are good leaving groups. Nucleophiles attack primary and secondary alkyl halides, displacing the leaving group in what is known as aliphatic, bimolecular nucleophilic substitution, the Sn2 reaction. The 8 2 reaction follows second-order kinetics, has a transition state rather than an intermediate, and proceeds via back-side attack of the nucleophile on the halide and inversion of configuration. 

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