Solvent-Dependent Divergent Cyclization of Bicyclo[1.1.0]butanes

Bicyclo[1.1.0]butanes (BCBs) have recently garnered significant research interest as versatile precursors for synthesizing potential [n.1.1] bioisosteres and multi-functionalized cyclobutanes in a straightforward and atom-economical manner. Here, we report a solvent-dependent divergent cyclization of BCBs that providecs highly diastereospecific decorated cyclobutanes and oxygen-containing bicyclo[3.1.1]heptanes (BCHeps), which serve as bioisosteres of meta-substituted arenes. This novel strategy employs precision-oriented control to achieve the desired divergence. Additionally, an unprecedented 1,2-difunctionalization reaction mode for BCBs was explore, expanding the available methods for efficiently exploring the chemical space of arene bioisosteres and highly functionalized cyclobutanes.