Solution-Phase Parallel Synthesis of a Multisubstituted Cyclic Imidate Library

The
solution-phase parallel synthesis of a diverse 71-member library
of multisubstituted cyclic imidates is described. The key intermediates,
3-iodomethylene-containing cyclic imidates, are readily prepared in
good to excellent yields by the palladium/copper-catalyzed cross-coupling
of various o-iodobenzamides and terminal alkynes,
followed by electrophilic cyclization with I2. These cyclic
imidates were further functionalized by palladium-catalyzed Suzuki–Miyaura,
Sonogashira, carbonylative amidation, and Heck chemistry using sublibraries
of commercially available building blocks.