Synthesis of CHF 2 -substituted 3-azabicyclo[3.1.0]hexanes by photochemical decomposition of CHF 2 -pyrazolines.

A practical synthesis of CHF 2 -substituted 3-azabicyclo[3.1.0]hexanes was developed for the first time. The key step was photochemical decomposition of CHF 2 -substituted pyrazolines. This protocol has the advantages of simple operation, and mild conditions, as well as excellent functional group tolerance, giving the desired products in moderate to excellent yields.