Copper-Free “Click” Modification of DNA via Nitrile Oxide−Norbornene 1,3-Dipolar Cycloaddition

Nitrile oxides react smoothly and rapidly with norbornene-modified DNA in a copper-free click reaction. The reaction allows high density functionalization of oligodeoxyribonucleotides (ODNs) with a large variety of molecules directly on solid supports and even in synthesizers without the need for an additional catalyst.