Enantioselective Synthesis - Chiral Auxiliary

Chiral Auxiliary

One enantioinduction strategy is the use of a chiral auxiliary, which forms an adduct to the starting materials and physically blocks the other trajectory for attack, leaving only the desired trajectory open. Assuming the chiral auxiliary is enantiopure, the different trajectories are not equivalent, but diastereomeric. The auxiliary shares problems similar to protecting groups; like protecting groups, auxiliaries require a reaction step to add and another to remove, increasing cost and decreasing yield.