Diazene-directed modular synthesis is described for the preparation Csp2-Csp3 and Csp3-Csp3 linkages where one or more stereogenic quaternary carbon centers are formed. The disclosed methods are directed to the preparation of compounds of Formula (I), or a pharmaceutically acceptable salt, tautomer or stereoisomer thereof, from compounds of Formula (II):wherein R1-R5 and q are as defined independently for each occurrence herein. A wide variety of compounds can be accessed in this manner, including oligocyclotryptamines, where the stereochemistry of each subunit is beneficially secured before fragment coupling.
