Short solution phase preparation of fused azepine-tetrazoles via a UDC (Ugi/de-Boc/cyclize) strategy

A novel application of the TMSN₃ modified Ugi 4-component reaction is disclosed for the solution phase synthesis of fused azepine-tetrazole libraries. The reaction of a N-Boc-α-amino aldehyde, secondary amine, methyl isocyanoacetate and trimethylsilylazide in methanol, followed by acid treatment, proton scavenging and reflux affords bicyclic azepine-tetrazoles. This efficient protocol, producing products with three diversity points, can be used to generate arrays of biologically relevant small molecules for general and targeted screening.