Halide with Lewis bases

Substitution can take place by the S l or the 8 2 mechanism elimination by El or E2 How can we predict whether substitution or elimination will be the principal reac tion observed with a particular combination of reactants The two most important fac tors are the structure of the alkyl halide and the basicity of the anion It is useful to approach the question from the premise that the characteristic reaction of alkyl halides with Lewis bases is elimination and that substitution predominates only under certain special circumstances In a typical reaction a typical secondary alkyl halide such as iso propyl bromide reacts with a typical Lewis base such as sodium ethoxide mainly by elimination... 

Interaction of Dihalogens and Hydrogen Halides with Lewis Bases 49... 

Legon AC (2007) The Interaction of Dihalogens and Hydrogen Halides with Lewis Bases in the Gas Phase An Experimental Comparison of the Halogen Bond and the Hydrogen Bond. 126 17-64... 

Taking into account the lability of the dimer with chloride bridges we suggest that butadiene attacks the bis(7r-crotylnickel chloride) with destruction of the halide bridges and formation of complexes like those formed by the interaction of crotylnickel halide with Lewis bases ... 

Fig. 4.3 Structures of some complexes of organotin halides with Lewis bases.

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