Conformation of 1-Oxy Cyclohexenes Deriving from Diels-Alder Cycloaddition: Spectroscopic and X-Ray Crystal Structure Analysis
作者:Donald W. Cameron、Robert W. Gable、Ross M. Heisey、Jonathan M. White
DOI:10.1071/ch00036
日期:——
For cycloadduct (6), derived by reaction of the (Z)-oxy diene (7) with thedienophile (8), the newly formed cyclohexene ring is shown by spectroscopicand X-raycrystalstructure analysis to be based on the half-chairconformation (9). This contrasts with analogous diastereomeric adducts from(E)-oxy dienes, which are based on the ring-flippedconformation (4). The determinant for this conformational difference
Reaction of Terminally Alkyl-Substituted Oxy Dienes with Tetracyanoethylene and Other Acceptors
作者:Donald W. Cameron、Ross M. Heisey
DOI:10.1071/ch00035
日期:——
dienes (4), (19) and (20) did not undergocycloaddition to 1,4-quinonoid dienophiles, for steric reasons, but allreacted with tetracyanoethylene to give [4+2]- or[2+2]-adducts. Unlike the 1-oxy diene (4), the 2- and 3-oxysystems (19) and (20) did not show hydrogen-transfer chemistry towardsquinones. The individual components of isomeric pairs of dienes (8), (9) and(19), (21) were differentiated by differing