Multiple-bond ionicity

Hydrogenation of Multiple Bonds with Metal Nanoparticles in Ionic Liquids... 

Other alkyl hypohalites usually add to carbon-carbon multiple bonds in a free-radical process.155-158 Ionic additions may be promoted by oxygen, BF3, or B(OMe)3.156-160 While the BF3-catalyzed reaction of alkyl hypochlorites and hypo-bromites gives mainly halofluorides,159 haloethers are formed in good yields but nonstereoselectively under other ionic conditions.156-158 160 In contrast, tert-BuOI reacts with alkenes in the presence of a catalytic amount of BF3 to produce 2-iodoethers.161 Since the addition is stereoselective, this suggests the participation of a symmetric iodonium ion intermediate without the involvement of carbocationic intermediates. 

In this chapter, we shall discuss substitution reactions that proceed by ionic or polar mechanisms in which the bonds cleave heterolytically. We also will discuss the mechanistically related elimination reactions that result in the formation of carbon-carbon multiple bonds ... 

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