Direct Coupling of Indoles with Carbonyl Compounds: Short, Enantioselective, Gram-Scale Synthetic Entry into the Hapalindole and Fischerindole Alkaloid Families

The invention of a method for the direct union of indoles and carbonyl compounds (ketones, amides, esters) is described. Using this new method, a short, enantioselective, gram-scale and protecting group-free synthetic entry to the fischerindole and hapalindole indole alkaloid family has been achieved from carvone and indole. Total syntheses of (+)-hapalindole Q and (−)-12-epi-fischerindole U isothiocyanate are reported. The absolute stereochemistry of the latter natural product has also been determined.