477909-73-2Relevant academic research and scientific papers
Selective synthesis of indazoles and indoles via triazene-alkyne cyclization switched by different metals
Fang, Yan,Wang, Chengming,Su, Shengqin,Yu, Haizhu,Huang, Yong
, p. 1061 - 1071 (2014/02/14)
We described two orthogonal heterocycle syntheses, where an arene bearing both an alkyne and a triazene functionality underwent two distinct cyclization pathways mediated by different transition metals. Starting from the same substrates, a synthesis of 2H
Deciphering the mechanistic dichotomy in the cyclization of 1-(2-ethynylphenyl)-3,3-dialkyltriazenes: Competition between pericyclic and pseudocoarctate pathways
Kimball, David B.,Weakley, Timothy J. R.,Herges, Rainer,Haley, Michael M.
, p. 13463 - 13473 (2007/10/03)
The mechanistic aspects of the cyclization of (2-ethynylphenyl)triazenes under both thermal and copper-mediated conditions are reported. For cyclization to an isoindazole, a carbene mechanistic pathway is proposed. The carbene intermediate can react with oxygen, dimerize to give an alkene, or be trapped either intermolecularly (using 2,3-dimethyl-2-butene to generate a cyclopropane) or intramolecularly (using a biphenyl moiety at the terminus of the acetylene to form a fluorene). Density-functional theory (DFT) calculations support a pseudocoarctate pathway for this type of cyclization. Thermal cyclization to give a cinnoline from (2-ethynylphenyl)triazenes is proposed to occur through a pericyclic pathway. DFT calculations predict a zwitterionic dehydrocinnolinium intermediate that is supported by deuterium trapping studies as well as cyclizations performed using a 2,2,6,6-tetramethylpiperidine moiety at the 3-position of the triazene.
