Orbital and Conformational Preferences in Rearrangements of 1-Phenyl-1-Propylidenes

✍ Scribed by B.A. Dellacoletta; H. Shechter

• Book ID: 104238055
• Publisher: Elsevier Science
• Year: 1979
• Tongue: French
• Weight: 266 KB
• Volume: 20
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)86720-4

✦ Synopsis

The stereochemistry of rearrangement of substituted 1-phenyl-1-propylidenes to trans and cis-propenylbenzenes is substituent dependent.

--A fascinating aspect of carbenes is the possible discrimination in the interactions of their non-bonded orbitals with substituents.l It has been suggested that electron-donor para substituents favor a planar conformation for a singlet phenylcarbene in order to stabilize its electron-deficient, carbene p orbita1.l Conversely, electron-withdrawing para substituents are presumed to enhance twisting of the phenyl group to a perpendicular conformation in which the electron-rich, carbene CI orbital is favorably deloca1ized.l A study is now reported of orbital and conformational effects in rearrangements of substituted 1-phenyl-1-propylidenes