An infrared study of the stereochemistry attending the Claisen rearrangement of cis-and trans-@, ydimethylallyl and two other related vinyl ethers has shown that the reaction produces essentially only trans substituted allylacetaldehydes. The double bond in the o- Claisen rearrangement product of trans-c~, r-dimethylallyl phenyl ether has also been demonstrated by infrared absorption to be predominantly trans. The transition state ...
