A direct method for the substitution of imidazo[1,5-a]pyridines at position 5

Product Class 5: Azaindolizines with Two Nitrogen Atoms in the Five-Membered Ring

“…Scheme 39 Lithiation of Imidazo[1,5-a]pyridines [159,160] In this section, aza analogues of 2 that contain additional nitrogen atoms in the six-membered ring will be discussed. These ring systems (imidazole-fused di-and triazines) are shown in Scheme 40.…”

One-Pot Three-Component Synthesis of Imidazo[1,5-<i>a</i>]pyridines

“…The classical method for synthesis of imidazo [1,5-a] pyridines mainly involves the use of 2-pyridylalkylamines with acylchlorides [5][6][7][8][9][10][11][12][13][14][15] and/or organic acids derivatives [16,17] in two step addition and cyclization. Besides these reactions, pereparation of imidazo [1,5-a] pyridines from 2-pyridylalkylamines with α,β-unsuturated compounds [18], and/or aldehydes [19] have been reported.…”

Synthesis and Photophysical Properties of 3-(Trifluoromethyl)-2H-imidazo[5,1-a]isoquinolinium Chloride Derivatives

“…1 For example, some imidazo[5,1-a]isoquinolinium salts have been approved for the treatment of diabetes as orally effective blood-sugar-lowering agents. 2 Various methods are used for the synthesis of these compounds, [3][4][5][6][7] but all involve multistep sequences and suffer from long reaction times or low yields. [4][5][6][7][8][9] Although the reaction of isocyanides with isoquinoline has been previously reported, 10 there is no reported procedure for the synthesis of trifluoromethylated imidazo [5,1-a]isoquinolinium chlorides.…”

“…2 Various methods are used for the synthesis of these compounds, [3][4][5][6][7] but all involve multistep sequences and suffer from long reaction times or low yields. [4][5][6][7][8][9] Although the reaction of isocyanides with isoquinoline has been previously reported, 10 there is no reported procedure for the synthesis of trifluoromethylated imidazo [5,1-a]isoquinolinium chlorides. In continuation of our search for new synthetic approaches to novel trifluoromethylated heterocyclic compounds, 11 we describe the synthesis of fluorescent 3-(trifluoromethyl)-2H-imidazo [5,1-a]isoquinolinium chlorides by the reaction of isoquinoline with trifluoroacetimidoyl chlo-rides and isocyanides.…”