The use of lanthanide‐induced shifts for conformational and structural studies of (R)‐MTPA (α‐methoxy‐α‐trifluoromethyl‐α‐phenylacetic acid) esters. 2—Complexes of the (R)‐MTPA esters of 4‐tert‐butylcyclohexanols with Eu(fod)₃

Abstract

It is shown that the complexation of the (R)-MTPA (a-methoxy-a-tduoromethyl-a-phenylacetic acid) ester of cis-4-tert-butylcyclohexanol with Eu(fod), is very similar to that of the corresponding trans-ester and ketones with Eu(fod),. Further evidence is provided that the MTPA moiety exists as two difierent rotamers. The LIS technique, used as a tool for structure and conformation elucidation, was found by means of a Monte Car10 error analysis not to be dependent on small experimental errors.