Modular synthesis of triazoles from 2-azidoacrylamides having a nucleophilic amino group.

Assembling methods using 2-azidoacrylamides having a nucleophilic amino group are disclosed. Divergent transformations of the amine-type trivalent platform were accomplished with a wide variety of electrophiles to obtain a broad range of 2-azidoacrylamides involving a fluorosulfonyl group-containing trivalent platform. Consecutive click conjugations including triazole formation, thiol-ene-type 1,4-addition, and SuFEx reactions realized the efficient assembly of easily available simple modules.

Iterative click reactions using trivalent platforms for sequential molecular assembly.

A facile synthesis of multi(triazole)s by iterative click reactions is disclosed. Good functional group tolerance of sequential click assembly by sulfur-fluoride exchange (SuFEx), copper-catalyzed azide-alkyne cycloaddition (CuAAC), and thia-Michael reaction realizes the iterative click reactions. Diverse multi(triazole)-type mid-molecules can be synthesized easily from readily available modules through good chemoselective reactions without functional group transformation steps.

Click assembly through selective azaylide formation.

An efficient triple-click assembly using a newly designed trivalent platform is disclosed. We achieved the selective azaylide formation of 2,3,5,6-tetrafluorophenyl azides with o-ester-substituted triarylphosphines leaving 2,6-dichlorophenyl azides untouched. Further rapid Staudinger reaction of dichlorophenyl azides and subsequent triazole formation allowed us to prepare trifunctionalized molecules in three steps.