Structural‐to‐Functional Complexity Transformations Enabled by Bridged Polyheterocycles: Access to Cis‐1,3‐Diamines and Amino‐Alcohols

Cis ‐1,3‐functionalized carbocycles and saturated heterocycles are ubiquitous motifs in natural products, pharmaceuticals, and bioactive compounds. Traditional synthetic approaches, relying on chiral pools or stepwise functionalization of acyclic precursors, often face challenges in stereocontrol and substitution diversity. Polyheterocyclic intermediates have emerged as powerful platforms to address these limitations by embedding multiple heteroatoms within rigid frameworks, enabling predictable stereochemical relay during subsequent transformations. This review highlights strategies that exploit such intermediates to access cis ‐1,3‐diamines, amino alcohols, and related motifs across four‐ to six‐membered rings and larger polycyclic systems. Key principles include facial shielding, stabilization of reactive intermediates, and selective functionalization driven by strain or symmetry‐breaking. Representative methodologies—cycloadditions, rearrangements, nucleophilic openings, C–H functionalizations, and ring homologations—allow rapid construction of densely functionalized scaffolds with multiple contiguous stereocenters from simple precursors. These approaches not only streamline access to stereodefined, highly substituted frameworks but also offer modularity for late‐stage diversification, making them highly valuable for medicinal chemistry, natural product synthesis, and the design of conformationally constrained building blocks.