Applications of Optically Pure Biphenyloxycyclohexanols in Deracemization of α-Substituted Aryloxypropanoic Acids by Dynamic Kinetic Resolution

Two derivatives of chiral trans-2-biphenyloxycyclohexanol were screened as chiral auxiliaries for the α-alkylation of aryloxypropanoic acids to obtain enriched enantiomers. The chiral auxiliary controls the enantioselective formation of α-aryloxypropanoic acids by dynamic kinetic resolution. The 2-phenylphenoxy derivative was found to be more effective in controlling chirality in the product as compared to its 4-phenylphenoxy isomer. Formation of the major isomer is supported by the calculation of their relative energies by computational analysis, using Gaussian 16.0 B3LYP/6-31+G(d) as a basis set.