NeoPHOX--an easily accessible P,N-ligand for iridium-catalyzed asymmetric hydrogenation: preparation, scope and application in the synthesis of demethyl methoxycalamenene.

Using a new class of chiral iridium hydrogenation catalysts, the antitumor natural product demethyl calamenene was synthesized in four steps in >20% overall yield and high enantiomeric purity.