Understanding Cu(ii)-based systems for C(sp³)–H bond functionalization: insights into the synthesis of aza-heterocycles

Abstract

Herein we report the synthesis of imidazo[1,5-a]pyridine heterocycles via a Cu(II)-mediated functionalization of α’-C(sp3)–H bonds of pyridinylaldimines and subsequent cyclization. This strategy exploits the inherent directing ability of heteroleptic aldimine...

Luminescent Imidazo[1,5‐a]pyridine Scaffold: Synthetic Heterocyclization Strategies‐Overview and Promising Applications

“…Very recently, M. Camats et al. reported the functionalization of pyridinylaldimine substrate with a catalytic approach employing copper bis‐pivalate and dichloro‐5,6‐dicyano‐1,4‐benzoquinone (as cyanating agent) obtaining imidazo[1,5‐a]pyridine‐1‐carbonitrile derivatives under microwave irradiation via a telescoped Cu‐catalyzed C(sp 3 )−H amination/cyclization followed by C(sp 2 )−H cyanation [58] …”

“…[55][56][57] Very recently, M. Camats et al reported the functionalization of pyridinylaldimine substrate with a catalytic approach employing copper bispivalate and dichloro-5,6-dicyano-1,4-benzoquinone (as cyanating agent) obtaining imidazo[1,5-a]pyridine-1-carbonitrile derivatives under microwave irradiation via a telescoped Cucatalyzed C(sp 3 )À H amination/cyclization followed by C(sp 2 )À H cyanation. [58] In 2005 J. Wang et al reported a direct cyclization of 2,2'dipyridylketone with different aromatic aldehydes in the presence of ammonium acetate for the synthesis of impy skeleton as a useful ligand (see Scheme 7).…”

Adamantane-type clusters: compounds with a ubiquitous architecture but a wide variety of compositions and unexpected materials properties

“…[µ4-O{Cu(MeOH)}4Cl6] (737) / DMF Q [394] [µ4-O{Cu(3-nonyl-8-fluoroimidazo[1,5-a]pyridine)}4Cl6] (757) [µ4-O{Cu(MeCN)}4Cl6] (707), 3-nonyl-8-fluoroimidazo[1,5-a]pyridine / MeCN, 100 °C, 10 min Q [440] [µ4-O{Cu(Amt)}4Cl6] (758) [Cu(α-CgPAmtHMe)(Cl)][BF4], KHMDS / THF J [441] [µ4-O{Cu(nmp)}3(CuOH2)Cl6] (759) CuCl, O2 / nmp, H2O F [442] [µ4-O{Cu(Me2NH)}3{Cu(dmso)}Cl6] (760)…”

Imidazopyridine Family: Versatile and Promising Heterocyclic Skeletons for Different Applications

“…Imidazo [4,5-b]pyridines are principally studied for the development of emissive products for OLEDs (organic light-emitting diodes) and sensor applications due to their excellent emissive properties [23][24][25][26][27][28]. 4.…”

“…Imidazo [4,5-b]pyridines are principally studied for the development of emi products for OLEDs (organic light-emitting diodes) and sensor applications d their excellent emissive properties [23][24][25][26][27][28]. 4. Imidazo [4,5-c]pyridines display a bioisosteric resemblance to the purine nuc manifesting similar structural and electronic properties.…”