Rh2(Piv)4-catalyzed denitrogenative coupling of pyrazoles with 1-sulfonyl-1,2,3-triazoles, smoothly form 2,6,8-triazabicyclo[3.2.1]octa-3,6-dienes via intramolecular aza-Diels–Alder cycloaddition. This domino reaction, combined with the subsequent thermal or acid-catalyzed rearrangement of the cycloadducts, provides direct and flexible access to N-sulfonylated (Z)-2-(2-aminovinyl)imidazoles.
1,4,8-Triazaocta-1,3,5,7-tetraenes,由 Rh 2 (Piv) 4催化的
吡唑与 1-磺酰基-
1,2,3-三唑的脱氮偶联原位生成,顺利形成 2 ,6,8-三
氮杂双环[3.2.1]octa-3,6-二烯通过分子内氮杂-Diels-Alder环加成反应。这种多米诺反应与随后的环加合物的热或酸催化重排相结合,提供了直接和灵活地获得N-磺酰化 ( Z )-2-(2-
氨基
乙烯基)
咪唑的途径。