Reactivity under Control

Significance

Highly stable quinacridinium derivatives 1 are transformed into reactive carbanions 3 by consecutive reduction and metalation. Intermediates 3 react readily with electrophiles, such as isothiocyanates, acid anhydrides, and hexyl ­iodide. Complete configuration retention has been proved by reacting (+)-2a with n-BuLi followed by benzyl isothiocyanate or methanol-d ₄.