Iec.-Butyl bromide

If 14 or more carbons are present, the product may be diamantane or a substituted diamantane. " These reactions are successful because of the high thermodynamic stability of adamantane, diamantane, and similar diamond-like molecules. The most stable of a set of C H isomers (called the stabilomer) will be the end product if the reaction reaches equilibrium. Best yields are obtained by the use of sludge catalysts (i.e., a mixture of AIX3 and ferf-butyl bromide or iec-butyl bromide).Though it is certain that these adamantane-forming reactions take place by nucleophilic 1,2-shifts, the exact pathways are not easy to unravel... 

Rinehart also used sandpapered zinc foil for the reaction of n-capronitrile with iec-butyl a-bromopropionate to produce rec-butyl a-n-caproylpropionate, but added a catalytic amount of cupric bromide. The ratio of zinc bromo ester nitrile was... 

It is often helpful, especially in a multistep reaction, to focus on the step that creates the stereogenic center. In the ionic addition of hydrogen bromide to 2-butene, for example, the stereogenic center is generated when bromide ion attacks iec-butyl cation. 

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