Rearrangement cyclobutylcarbinyl—cyclopentyl

The synthesis of (+ )-isocomene is another good example showing the versatility of the cyclobutylcarbinyl cation — cyclopentyl cation rearrangement. A high yield of isocomene (286) was obtained when the olefin (285) was treated with pTsOH in benzene97 . 

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