Polycyclic azines. III. Synthesis of 3‐aminoimidazo[1,5‐a]pyridine derivatives by cyclodesulfurization of N′‐Substituted‐N‐(2‐pyridylmethyl)thioureas with dicyclohexylcarbodiimide

Abstract

A series of 3‐substituted aminoimidazo[1,5‐a]pyridine derivatives have been synthesized by cyclodesulfurization of a variety of N′‐substituted‐N‐(2‐pyridylmethyl)thioureas with dicyclohexylcarbodiimide (DCCD). 1H Nmr spectral analysis of all synthesized compounds is given.

Metal-Mediated Controllable Creation of Secondary, Tertiary, and Quaternary Carbon Centers: A Powerful Strategy for the Synthesis of Iron, Cobalt, and Copper Complexes with in Situ Generated Substituted 1-Pyridineimidazo[1,5-a]pyridine Ligands

“…The common access to imidazo[1,5- a ]pyridine and its derivatives involves Vilsmeier-type cyclizations of N -2-pyridylmethylamides, cyclizations of N -2-pyridylmethylthioamides, and condensation of 2,2′-pyridil (or 2,2′-dipyridyl ketone), aldehydes, and ammonium acetate . The coordination complexes of imidazo[1,5- a ]pyridine and its derivatives are routinely generated via the traditional direct synthesis of metal ions and ligands.…”

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.…”

Convenient Preparation of a Novel Class of Imidazo[1,5-a]pyridines: Decisive Role by Ammonium Acetate in Chemoselectivity

“…The previous synthesis of imidazo[1,5- a ]pyridines mainly involves the use of α-2-pyridylalkylamine, followed by subsequent functionalization to anchor various electrophilic reagents. ,− Other approaches include the use of imine derivatives, 2-cyanopyridine, and recently, benzotriazoles . Most syntheses require strict reaction conditions because of the use of highly sensitive reagents such as LDA, MeLi, TiCl 4 , dicyclohexylcarbodiimide (DCC), phosphoric oxychloride, , or PCl 5 . The formation of the fused ring framework usually takes two or more steps to complete.…”