Kinetic Resolution of Aryl Alkanols by Homobenzotetramisole

Significance

The synthesis of homobenzotetramisole (HBTM) 1 and homotetramisole (HTM) 2 from a chiral γ-aminoalcohol is reported. These thiazoline derivatives, especially HBTM 1, proved to be efficient catalysts for the kinetic resolution of different α-aryl alkanols such as 3. In the presence of acetic anhydride and base, selectivities of up to 122:1 and conversions of up to 58% could be achieved for 12 examples. However, the chemo­selectivities for substrates with an aryl group in β-position to the hydroxyl group or with non-aryl substituents were low. This supports the provided mechanism involving π-stacking in the transition state.