General Experimental Hints and Obstacles

Although analytical chemistry has made giant strides forward in the last 100 years, separation by column chromatography can still be difficult. Certain cinchona 

No iminium resonance, less driving force -Prototype not yet observed 

Migratory aptitude depends on configuration at C9, conformation, stereoelectronic factors, leaving group ability, solvation and acidity (protonation of bridgehead nitrogen). 

9-ep/-quinine Pseudo-enantiomeric quinidines react analogously. 

So far, cinchona chemistry has focused mainly on applications as chiral ligands and chiral organocatalysts. Chemical alterations in alkaloids have usually been a minor issue and also unfashionable in this context. In fact, the first 10 chapters of this handbook provide many impressive examples for these applications, but there is more to the chemistry of cinchona alkaloids than that. New reactions and new structures have come to light only recently in both fundamental and applied works. Landmark developments are 

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