CONFIGURATIONAL AND CONFORMATIONAL STUDY OF NEW ESTERS DERIVED FROM 2-METHYL-2-AZABICYCLO[2.2.2]OCTAN-5-SYN(ANTI)-OLS BY NMR-SPECTROSCOPY AND X-RAY CRYSTALLOGRAPHY .1.

A series of esters derived from syn- and anti-2-methyl-2-azabicyclo [2 .2.2]octan-5-ols were synthesized and studied by H-1, C-13 and 2D NMR spectroscopy, The crystal structure of syn-(3,5-dichlorobenzoyloxy)-2- methyl-2-azabicyclo [2.2.2]octane was determined by x-ray diffraction. The unambiguous assignment of all bicyclic proton and carbon resonanc es was achieved by the combined analysis of the H-1-C-13 correlation s pectra and double resonance experiments. The H-1-H-1 coupling constant s are proposed as model values in order to carry out the analysis of o ther isoquinuclidine derivatives. In order to gain additional informat ion, a conformational analysis using molecular modeling techniques was undertaken. (C) 1997 John Wiley & Sons, Ltd.