An efficient approach to bridged-bicyclic rings via intramolecular diazo ketone insertion

A regioselective intramolecular diazo ketone insertion reaction of chiral cyclohexenones is described. The methodology shows potential utility in the syntheses of bicyclo[4.2.1]nonan-9-one, bicyclo[4.3.1]decan-10-one and cyclooctanoid rings.