Synthesis of bridged polycyclic ring systems via carbene cascades terminating in C-H bond insertion.

A carbene cascade reaction that constructs functionalized bridged bicyclic systems from alkynyl diazoesters is presented. The cascade proceeds through diazo decomposition, carbene/alkyne metathesis, and C-H bond insertion. The diazoesters are easily synthesized from cyclic ketones. Substrate ring size and substitution patterns control the connectivity and diastereomeric preference found in the products.