General chiral route to irregular monoterpenes via a common intermediate: syntheses of (S)-lavandulol, cis(1S,3R)-chrysanthemol, (1R,2S)-rothrockene, and (R)-santolinatriene
Matsui et al., Journal of the Agricultural Chemical Society of Japan, 1956, vol. 20, p. 89,91
作者:Matsui et al.
DOI:——
日期:——
Electron Transfer Photochemistry of Chrysanthemol: An Intramolecular S<sub>N</sub>2‘ Reaction of a Vinylcyclopropane Radical Cation
作者:Torsten Herbertz、Heinz D. Roth
DOI:10.1021/ja953596c
日期:1996.11.13
The electron transfer photochemistry of optically pure (1R,3S)-(f)-cis-chrysanthemol (cis-2) results in the formation of (R)-5-(1-(p-cyanophenyl)-1-methyethyl)-2,2-dimethyl oxacyclohex-3-ene (4) with significant retention of optical activity. The product is rationalized via nucleophilic attack of the alcoholic function of the radical cation on the terminal carbon of the vinyl group with simultaneous replacement of an isopropyl radical as an intramolecular leaving group in an apparent S(N)2' reaction. This mode of attack is unprecedented in vinylcyclopropane radical cations and is interpreted as evidence for the significant role that relief of ring strain and its avoidance play in determining the course of nucleophilic capture in radical cationic systems.
Chrysanthemylcarbenes. Isobutenyl substituent effect and conformational control in cyclopropylcarbene rearrangements