Q36E
Question
Photolysis of the cis-cyclobutene isomer in Problem 30-35 yields cis-cyclododecaen-7-yne, but photolysis of the trans isomer yields trans-cyclododecaen-7-yne. Explain these results, and identify the type and stereochemistry of the pericyclic reaction.
Step-by-Step Solution
Verified Answer
Photolysis of cis-cyclobutene isomer occurs in disrotatory manner in photochemical conditions while that of trans- cyclobutene isomer occurs in conrotatory manner.
1Step 1: Photolysis of the cis-Cyclobutene Isomer
Photolysis of cis-cyclobutene isomer occurs in a disrotatory manner in photochemical conditions, as shown below:
2Step 2: Photolysis of the trans-Cyclobutene Isomer
Photolysis of trans-cyclobutene isomer occurs in conrotatory manner in photochemical conditions, as shown below:
trans-Cyclododecaen-7-yne
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