116856-96-3Relevant articles and documents
Synthesis, characterization, and cycloaddition reactivity of a monocyclic aromatic 1,2,3,5-tetrazine
Wu, Zhi-Chen,Boger, Dale L.
supporting information, p. 16388 - 16397 (2019/10/16)
Herein we disclose the synthesis and full characterization of the first monocyclic aromatic 1,2,3,5-tetrazine, 4,6-diphenyl-1,2,3,5-tetrazine. Initial studies of its cycloaddition reactivity, mode, regioselectivity, and scope illustrate that it participates as the 4π-component of well-behaved inverse electron demand Diels-Alder reactions where it preferentially reacts with electron-rich or strained dienophiles. It was found to exhibit an intrinsic reactivity comparable to that of the isomeric 3,6-diphenyl-1,2,4,5-tetrazine, display a single mode of cycloaddition with reaction only across C4/N1 (no N2/N5 cycloaddition observed), proceed with a predictable regioselectivity (dienophile most electron-rich atom attaches to C4), and manifest additional reactivity complementary to the isomeric 1,2,4,5-tetrazines. It not only exhibits a remarkable cycloaddition reactivity, surprisingly good stability (e.g., stable to chromatography, long-term storage, presence of H2O even as reaction co-solvent), and broad cycloaddition scope, but it also displays powerful orthogonal reactivity with the 1,2,4,5-tetrazines. Whereas the latter reacts at extraordinary cycloaddition rates with strained dienophiles (tetrazine ligation), the new and isomeric 1,2,3,5-tetrazine displays similarly remarkable cycloaddition rates and efficiencies with amidines (1,2,3,5-tetrazine/amidine ligation). The crossover reactivities (1,2,4,5-tetrazines with amidines and 1,2,3,5-tetrazines with strained dienophiles) are sufficiently low to indicate they may be capable of use concurrently without competitive reactions.
1,2,3,5-Tetrazines and 1,2,3-triazaspirononanes: Remarkable Products from 1,3-Dipolar Cycloadditions of N-Sulphinylamines with Substituted Triazolium Imides
Butler, Richard N.,Cunningham, D.,McArdle, Patrick,O'Halloran, Gerald A.
, p. 232 - 234 (2007/10/02)
Cycloadditions of aryl-N-sulphinylamines with substituted triazolium imides gave new 8?-2,4,5,6-tetrasubstituted-1,2,3,5-tetrazines, the X-ray crystal structure 1,6>decenes are suspected as intermediates and attempts to intercept them led to new substituted 1,2,3-triazaspirononanes, the X-ray crystal structure of one of which is reported.