N-Heterocycle construction via cyclic sulfamidates. Applications in synthesis

When combined with an appropriate nucleophilic component, 1,2- and 1,3-cyclic sulfamidates function as versatile precursors to a range of substituted and enantiopure heterocyclic classes. Functionalised enolates provide a direct entry to C-3 functionalised lactams, as exemplified by total syntheses of (-)-aphanorphine, (+)-laccarin and (-)-paroxetine. Heteroatom nucleophiles, such as thiol esters, amino esters and bromo phenols, provide concise access to a range of enantiomerically pure thiomorpholine, piperazine and benzofused heterocyclic scaffolds. The latter methodology enables a facile synthesis of the antibacteriocidal agent levofloxacin.