Bond strengths, carbon-halogen

The rate of elimination depends on the halogen the reactivity of alkyl halides increasing with decreasing strength of the carbon-halogen bond... 

The strength of their carbon-halogen bonds causes aryl halides to react very slowly in reactions in which carbon-halogen bond cleavage is rate determining as m nude ophilic substitution for example Later m this chapter we will see examples of such reactions that do take place at reasonable rates but proceed by mechanisms distinctly dif ferent from the classical S l and 8 2 pathways... 

The unusual carbon-halogen bond strength in vinyl halides compared to saturated alkyl halides has been ascribed to partial double-bond character (103, 104) coupled with increased a-bond strength (105) due to differences in... 

Table 6.1 Carbon-Halogen Bond Lengths, Bond Strength and Dipole Moment...

There is substantial data to support reaction sequence [2] and some data suggesting sequence [3] (21, 22) may occur under certain pyrolysis conditions, but no evidence has been published for [3] in the absence of a large excess of polymer substrate. In the case of [2] and [3] it has been suggested that these reactions would be dependent on the carbon-halogen bond strength in the organohalogen component (9). 

The strength of carbon-halogen bonds decreases more from C—F to C—I than the corresponding decrease from M—F to M—I in most... 

The toxicities of those perhalogenated iodoalkanes used in industrial telomerization processes, in laser-based nucleus fusion research and for other applications have been published in some detail (Table 16). The short chain linear perfluoroiodoalkanes are nontoxie. Branching of the carbon backbone and lower bond strength of the halogens involved are responsible for higher biological activity, observed in some cases. The higher linear perfluorinated iodoalkanes are completely inert materials. 

TABLE 8. Strengths of carbon-halogen bonds, in kcal mol1 a... 

Bond strengths decrease with increasing size of the halogen bonded to carbon. 

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