A facile convergent access to the important indole alkaloid (+)-harmicine is described,
starting from tryptamine and (R)-acetoxysuccinic anhydride via the corresponding acetoxysuccinimide in very good
overall yield. Regioselective reduction of an unsymmetrical imide carbonyl group and
acid-catalyzed stereoselective intramolecular cyclization were the key features involved.
The directing group to induce asymmetry was finally detached via the corresponding
iodide by using tributyltin hydride chemistry.
Key words
imides - reduction - cyclization - stereoselective synthesis - alkaloids