Über atropisomere Biphenyl-Derivate mit einer Pseudoasymmetrieachse

Diastereomeric biphenyl derivatives VIIIa and b have been prepared as first examples of compounds with an axis of pseudoasymmetry. Compound VIIIa was prepared by an unambiguous synthesis from (+)-V. The absolute configuration of the latter was determined by correlation with (+)-(R)-2-amino-2′,6-dimethyl-6′-nitro-biphenyl (XII) and hence the configuration of VIIIa (and therefore also of VIII b) was established.