Photochemical Formation of Dibenzosilacyclohept-4-yne for Cu-Free Click Chemistry with Azides and 1,2,4,5-Tetrazines.
Photochemical generation of dibenzosilacyclohept-4-yne 3 from the corresponding cyclopropenone 1 and its copper-free click reactions are reported. Steady-state irradiation, kinetic, and transient absorption spectroscopy studies revealed that strained alkyne 3 is rapidly (<5 ns) and efficiently (Φ = 0.58-0.71) photoreleased from 1 and undergoes remarkably fast, selective, and high-yielding 1,3-dipolar cycloaddition with benzyl azide (∼20 M-1s-1) or [4 + 2] inverse-electron-demand Diels-Alder reaction with 1,2,4,5-tetrazines (∼260 M-1s-1) in both methanol and acetonitrile.
Department of Chemistry and RECETOX, Masaryk University , Kamenice 5, 625 00 Brno, Czech Republic.
Marek
M
Martínek
Department of Chemistry and RECETOX, Masaryk University , Kamenice 5, 625 00 Brno, Czech Republic.
Lenka
L
Filipová
Department of Chemistry and RECETOX, Masaryk University , Kamenice 5, 625 00 Brno, Czech Republic.
Juraj
J
Galeta
Department of Chemistry and RECETOX, Masaryk University , Kamenice 5, 625 00 Brno, Czech Republic.
Lucie
L
Ludvíková
Department of Chemistry and RECETOX, Masaryk University , Kamenice 5, 625 00 Brno, Czech Republic.
Petr
P
Klán