Parallel asymmetric total syntheses of eliglustat and C2-epi-eliglustat are reported. Both approaches feature a common key step, which involves a stereocontrolled TMSOTf-mediated aldol-like reaction of azidoacetyl thioimides with dibenzyl acetals of aromatic aldehydes catalyzed by chiral nickel(II) complexes. It is worth noting that the structure of dibenzyl acetals plays a key role in the stereochemical outcome of some of these reactions, as supported by theoretical calculations. Overall, this strategy enables the independent manipulation of the amino and hydroxy functional groups and favors the isolation of enantiomerically pure products.
Mellado-Hidalgo et al. (Mon,) studied this question.