Dynamically resolved peri-substituted 2-formyl naphthamides: a new class of atropisomeric chiral auxiliary

2-Formyl-N,N-dialkylnaphthamides are chiral, atropisomeric compounds, provided they are substituted peri to the amide group. They may be obtained as single enantiomers by dynamic resolution on formation of diastereoisomeric aminal derivatives and used as chiral auxiliaries in a new addition/rearrangement strategy. Nucleophilic attack by vinyl anion equivalents in the presence of Lewis acids leads atroposelectively to single diastereoisomers of allylic alcohols, whose derivatives undergo stereospecific [3,3]-sigmatropic rearrangements. Reductive ozonolysis of the rearrangement product returns an enantiomerically pure functionalised alcohol and in principle allows recovery of the atropisomeric auxiliary.