Microwave-assisted synthesis of 3-formyl substituted imidazo[1,2-a]pyridines

Synthesis and Antimicrobial Evaluation of 2-(6-Imidazo[1,2-a]pyridin-2-yl-5-methyl-2,4-dioxo-3-phenyl-3,4-dihydrothieno[2,3-d]pyrimidin-1(2H)-yl)-N-arylacetamide Derivatives

“…The most common route for the preparation of imidazo[1,2-a]pyridines is the reaction of 2-aminoazines with α-haloketones [15][16][17][18]. As a part of our research on the construction of 6-heteryl-5-methylthieno [2,3-d]pyrimidin-2,4(1H,3H)-diones, we studied the interaction of the readily synthetically available 6-(bromoacetyl)-5-methyl-3-phenylthieno [2,3-d]pyrimidine-2,4(1H,3H)-dione 1 [3] with 2-aminopyridine.…”

Functionalization of the imidazo[1,2-a]pyridine ring in α-phosphonoacrylates and α-phosphonopropionates via microwave-assisted Mizoroki–Heck reaction

“…The Mizoroki-Heck reaction-assisted functionalization of 6-bromoimidazo[1,2-a]pyridine-3-carbaldehyde [12], a precursor of compounds 1 and 2, was successfully achieved. We used tri(o-tolyl)phosphine (P(o-tol) 3 , palladium(II) acetate (Pd(OAc) 2 ) and obtained the desired product (E)-benzyl 3-(6- Recently, multiple variants for the application of microwave heating for conducting Mizoroki-Heck reactions have been reported, including the use of heterogeneous and homogeneous catalysts, as well as continuous-flow conditions [13][14][15].…”

Recent Advances in the Synthesis of Imidazo[1,2‐a]pyridines: A Brief Review

“…The imidazo[1,2‐ a ]pyridine 3‐carbaldehydes are common scaffolds used for the incorporation of various heterocycles into diverse structures [196] . The various reported methods towards the synthesis of imidazo[1,2‐ a ]pyridine 3‐carbaldehydes has many drawbacks including long reaction times (10–24 h), heating at 100 °C or higher temperatures, use of oxygen gas and metal catalysts, pre‐formation of the substrates, low yields and the formation of unidentified side‐products [197] .…”

“…[196] The various reported methods towards the synthesis of imidazo[1,2-a]pyridine 3-carbaldehydes has many drawbacks including long reaction times (10-24 h), heating at 100 °C or higher temperatures, use of oxygen gas and metal catalysts, pre-formation of the substrates, low yields ChemistrySelect and the formation of unidentified side-products. [197] Kusy et al [196] in 2019 reported an efficient, metal-free microwaveassisted method for the synthesis of 3-formyl imidazo[1,2a]pyridines 263 from 2-amino pyridine 261 and bromomalonaldehyde 262 in good to excellent yields. The reaction mechanism proceeds via attack of the exocyclic amine group on bromomalonaldehyde 262 followed by the elimination of water and formation of an intermediate imine A or enamine B.…”