Proton exchange reactions in isotope chemistry (II) synthesis of stable isotope‐labeled LCQ908

The proton exchange reaction was applied to the preparation of stable isotope-labeled LCQ908. For this synthesis, a suitable intermediate with protons alpha to a carbonyl group was first subjected to the H-D exchange reaction; subsequent coupling of a carbonyl group with [(13)C2 ]triethyl phosphonoacetate, followed by hydrogenation and hydrolysis, led to the stable labeled compound. Incorporation of two carbon-13 atoms in the molecule eliminated the presence of undesired M+0.