Synthesis of (R)-[2-2H]isopentenyl diphosphate and determination of its enantiopurity by 2H NMR spectroscopy in a lyotropic medium

[formula: see text] The synthesis of (R)-[2-2H]isopentenyl diphosphate from D-mannitol 1,2:5,6-bis-acetonide in 10 steps is reported. Stereospecific incorporation of the label is achieved by a BF3-catalyzed NaCNBD3 reduction of the enantiomerically pure (S)-isopropylidene oxirane intermediate. The enantiomeric excess of the penultimate precursor [2-2H]isopentenyl tosylate (> 95% ee) was determined by 2H NMR spectroscopy in a poly-gamma-benzyl-L-glutamate/CH2Cl2 liquid crystal at -50 degrees C.