Extension of hydrogen borrowing alkylation reactions for the total synthesis of (–)-γ-lycorane

Hall C, Marriott I, Christensen K, Day A, Goundry W, Donohoe T

The total synthesis of (–)-γ-lycorane (10 steps) and synthesis of (±)-
γ-lycorane (8 steps) was completed from cyclohexenone. A new
two step hydrogen borrowing alkylation of an aziridinyl alcohol,
coupled with a Ph* deprotection/cyclisation procedure was
developed for de novo formation of the fused 6,5 heterocyclic ring.
This work is one of the first examples of hydrogen borrowing C-C
bond formation being used as a key step in a total synthesis project.