Exhibit 30-9 Vitamin D₃,cholecalciferol,is Synthesized Under the Skin by the Photochemical Pericyclic

question 4

Multiple Choice

Exhibit 30-9
Vitamin D₃,cholecalciferol,is synthesized under the skin by the photochemical pericyclic process shown below.Answer the following question(s) about these reactions.
-Refer to Exhibit 30-9.The first step in this process is a(n) :

• A)sigmatropic rearrangement
• B)cycloaddition reaction
• C)annulation reaction
• D)electrocyclic reaction

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