Combined coinage metal catalysis for the synthesis of bioactive molecules

The use of the coinage metals copper, silver, and gold enables an efficient and stereoselective assembly of bioactive heterocycles via allenic intermediates. The synthesis of functionalized allenes by S(N)2'-substitution or S(N)2'-reduction is mediated or catalyzed by copper, whereas silver and gold are the catalysts of choice for subsequent 5- or 6-endo-cyclizations. Overall, this sequence proceeds with efficient center-to-axis-to-center chirality transfer.