Steric effects in the meta photocycloaddition of ethylenes to alkylbenzenes
โ Scribed by Andrew Gilbert; Peter Heath
- Publisher
- Elsevier Science
- Year
- 1979
- Tongue
- French
- Weight
- 225 KB
- Volume
- 20
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
๐ SIMILAR VOLUMES
Secondary deuterium isotope effects were observed in the meta photocycloaddition
The effect of substitution of hydrogen by deuterium in some aromatic compounds on product distributions in the meta photocycloaddition to al kenes was investigated. The isotope effects found are in agreement with a polar mechanism.
The role of steric effects in photocycloaddition reactions has received relatively little attention, and, at best, the published results are ambiguous. For example, photocycloaddition of benzophenone (\_1, Rx-R, =C,Hc) to norbornene (5, X-H) is reported to lead to the E-adduct ,3 (R1=R,= CsHs X=H) a
The unusual stability of phenylsulfinyl carbene, signalled by (1) the ease by which it is formed unimolecularly from phenyl diazomethyl sulfoxide, (2) the lack of C-H insertion reactions, and (3) the high degree of stereoselectivity in cycloaddition to Z-2-butene and cyclohexene, 2 strongly suggests