Synthesis of 3‐quinuclidinol‐ 18 O, benzilic‐d 5 acid, and 3‐quinuclidinyl‐ 18 O benzilate‐d 5

Isotopically labeled analogs of 3‐quinuclidinol (Q), benzilic acid (BA), and 3‐quinuclidinyl benzilate (BZ), for use as internal standards for isotope dilution measurements and the labeled intermediates 3‐quinuclidinone and methyl benzilate used in their production, were synthesized. The isotopic purities of the 1‐azabicyclo[2.2.2]octan‐3‐ 18 O‐ol, α‐hydroxy‐a‐phenyl‐d 5 ‐benzeneacetic acid, and 3‐quinuclidinyl‐ 18 O benzilate‐d 5 were determined and the electron impact ionization mass spectrum was obtained for each.