Despite the growing application of tetrazine bioorthogonal chemistry, it is still challenging to access tetrazines conveniently from easily available materials. Described here is the de novo formation of tetrazine from nitriles and hydrazine hydrate using a broad array of thiol‐containing catalysts, including peptides. Using this facile methodology, the syntheses of 14 unsymmetric tetrazines, containing a range of reactive functional groups, on the gram scale were achieved with satisfactory yields. Using tetrazine methylphosphonate as a building block, a highly efficient Horner–Wadsworth–Emmons reaction was developed for further derivatization under mild reaction conditions. Tetrazine probes with diverse functions can be scalably produced in yields of 87–93 %. This methodology may facilitate the widespread application of tetrazine bioorthogonal chemistry.

Despite the growing application of tetrazine bioorthogonal chemistry,itisstill challenging to access tetrazines conveniently from easily available materials.Described here is the de novo formation of tetrazine from nitriles and hydrazine hydrate using ab road array of thiol-containing catalysts, including peptides.Using this facile methodology,the syntheses of 14 unsymmetric tetrazines,c ontaining ar ange of reactive functional groups,o nt he gram scale were achieved with satisfactory yields.U sing tetrazine methylphosphonate as ab uilding block, ah ighly efficient Horner-Wadsworth-Emmons reaction was developed for further derivatization under mild reaction conditions.T etrazine probes with diverse functions can be scalably produced in yields of 87-93 %. This methodology may facilitate the widespread application of tetrazine bioorthogonal chemistry.

A series of BODIPY probes with a wide emission range were prepared via aminoacylation at the meso-position. Functional moieties were also introduced to induce bathochromic shifts in emission, improve water solubility, increase Stokes shifts, and construct bioorthogonal turn-on probes. The developed analogues were successfully used in live-cell imaging, suggesting that the described strategy can be used to prepare probes with improved bioimaging potential.