2-Bromo-2-methylbutane hydrolysis

Additional evidence for carbocation intermediates in certain nucleophilic substitutions comes from observing rearrangements of the kind normally associated with such species For example hydrolysis of the secondary alkyl bromide 2 bromo 3 methylbutane yields the rearranged tertiary alcohol 2 methyl 2 butanol as the only substitution product... 

Why does the carbocation intermediate in the hydrolysis of 2 bromo 3 methylbutane rearrange by way of a hydride shift rather than a methyl shift ... 

We have already noticed (p. 86) that the SN2 hydrolysis of 1-bromo-2,2-dimethylpropane (neopentyl bromide, 24) is slow due to steric hindrance. Carrying out the reaction under conditions favouring the Sjyl mode can result in an increased reaction rate but the product alcohol is found to be 2-methylbutan-2-ol (26) and not the expected... 

Problem 7.27 How does the S l mechanism for the hydrolysis of 2-bromo-3-methylbutane, a 2° alkyl bromide, to give exclusively the 3° alcohol 2-methyl-2-butanol. establish a carbocation intermediate ... 

Reaction of 3-bromo-3-methylbutan-2-one with triphenylmethylhydrazine and potassium thiocyanate in acetic acid gives 7,7,7a-trimethyl-2,3,5,6,7,7a-hexahydro-li/-imidazo[l,5-Z>][l,2,4]-tri-azole-2,5-dithione (381b) due to the facile hydrolysis the triphenylmethyl group. <95FES379>. 

Carbocation Rearrangement in the SnI Hydrolysis of 2-Bromo-3-methylbutane THE OVERALL REACTION ... 

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