The next 2 slides are part of one question.. Which of the following is not a step in the mechanism of the given reaction?

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Presentation transcript:

The next 2 slides are part of one question.

Which of the following is not a step in the mechanism of the given reaction?

a. b. c. d.

Biosynthesis of Steroids “Biosynthesis” of steroids involves both addition of carbocation to alkene (as seen in cationic polymerization) and carbocation rearrangements. (The next 10 slides show the mechanistic steps in the conversion of squalene oxide to lanosterol and asks what types of reactions are occurring.)

Epoxide (oxirane) acid catalyzed ring opening

Starting with squalene oxide and ending lanosterol, –How many mechanistic steps involve carbocation rearrangements? –How many mechanistic steps involve  addition to a carbocation?