Special Topic Rearrangements in Biological Processes

PROBLEM 9.22 Devise syntheses for the following molecules from 2-methyl-2-hutene. You may also use any inorganic reagent as well as organic compounds containing no more than one carbon. 

The hydride shifts and alkyl migrations discussed in Section 9.9 are not arcane examples fit only for the nether regions of an organic text (and for especially vexing problems). They are going on all the time as part of many of the enzyme-driven reactions in your body. So, as you read this, hydrides are migrating somewhere deep inside you. 

FIGURE 9.70 The final product of the methylation of oleate is 10-methylstearate. 

FIGURE 9.71 This deuterium labeling experiment shows that there is a hydride shift at the center of this reaction. 

The central topic of this chapter is the addition of HX molecules to alkenes. These reactions begin by the addition of the positive end of the dipole (the electrophile) to the alkene (the nucleophile) in such a way as to form the more stable carbocation. The anion (X ) then adds to the cation to form the final addition product. The direction of addition—the regiochemistry 

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