Tert-Butyl cation hydrogen chloride

The major difference between the two mechanisms is the second step The second step m the reaction of tert butyl alcohol with hydrogen chloride is the ummolecular dis sociation of tert butyloxonium ion to tert butyl cation and water Heptyloxonium ion however instead of dissociating to an unstable primary carbocation reacts differently It IS attacked by bromide ion which acts as a nucleophile We can represent the transition state for this step as... 

These common features suggest that carbocations are key intermediates m alcohol dehydra tions just as they are m the reaction of alcohols with hydrogen halides Figure 5 6 portrays a three step mechanism for the acid catalyzed dehydration of tert butyl alcohol Steps 1 and 2 describe the generation of tert butyl cation by a process similar to that which led to its for matron as an intermediate m the reaction of tert butyl alcohol with hydrogen chloride... 

H2O2—hydrogen peroxide HRP—horseradish peroxidase PVP—poly(4-vinylpiridine) CpFeC2B9Hii—3i-cyclopentadiennyl-3i-dicarbollyliron Ru(NH3)5py(PFg)—pentaammine-pyridineruthenium(II) ttb-CuPc— tetra-tert-butyl-copper phtalocyanine GA—glutaraldehyde BSA—bovine serum albumin mPEG—methoxypolyethylene [Os(bpy)2pyCl] -—Osmium dibypyridine pyridine chloride cation. 

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