Synthetic strategy towards halometallates with imidazo[1,5-a]pyridinium-based counterions

Abstract

<p>Organic-inorganic halometallates is a very promising class of compounds within the more general domain of organic-inorganic hybrid materials. The efficient approach for creating new hybrid halometallate salts is the design...</p>

Organic–inorganic hybrid tetrachlorocadmates as promising fluorescent agents for cross-linked polyurethanes: synthesis, crystal structures and extended performance analysis

“… 17–19 Encouraged by the successful incorporation of the imidazo[1,5- a ]pyridinium moiety in the halometallate structure that produced the fluorescent [L] 2 [ZnCl 4 ] hybrid salt (L + -2-methyl-3-(pyridin-2-yl)imidazo[1,5- a ]pyridinium cation), 20 we developed a convenient synthetic strategy to systematically modify the photoluminescent properties of imidazo[1,5- a ]pyridine species through varying substituents on the polyheterocyclic core as well as through introducing different metal ions. 21 The next cation in the series, 2-methylimidazo[1,5- a ]pyridinium, [L′] + , has been synthesized by the interaction between equimolar amounts of formaldehyde, methylamine hydrochloride and 2-pyridinecarbaldehyde (2-PCA) in an aqueous solution.…”

Organic–inorganic hybrid mixed-halide ZnII and CdII tetrahalometallates with the 2-methylimidazo[1,5-a]pyridinium cation

“…The very similar IR spectra of hybrid salts (I)-(III) show a distinctive pattern we consider characteristic of the L + cation (Vassilyeva et al, 2020) (Fig. 4).…”

“…Protons of the CH 3 group are observed as singlets at 4.26/4.24/4.25 ppm. The close resemblance of the measured 1 H NMR spectra with those of other L + -containing halometallates (Vassilyeva et al, 2020(Vassilyeva et al, , 2021 implies that the L + cation is conformationally stable in solutions of both hybrid salts, which are thus dissociated in DMSO. ] 2 [ZnCl 3.19 I 0.81 ], [L] 2 [CdBr 2.42 Cl 1.58 ] and [L] 2 [CdCl 3.90 I 0 The room-temperature 1 H NMR spectrum of (III) in DMSO-d 6 in the 10-4 ppm range.…”

“…The 2-methylimidazo[1,5-a] pyridinium cation, L + , has been synthesized from the oxidative cyclocondensation of equimolar amounts of formaldehyde, methylamine hydrochloride and 2-pyridinecarbaldehyde in an aqueous solution. The incorporation of L + in the metal chloride structure reduced the dimensionality of the PbCl 2 3-D perovskite framework to a 1-D stepwise chloroplumbate(II) wire arrangement in [L] n [PbCl 3 ] n1 and produced [L] 2 [MCl 4 ] (M = Zn, Cd) hybrid salts with tetrahedral anions (Vassilyeva et al, 2020(Vassilyeva et al, , 2021. The three compounds exhibited intense sky blue-light photoluminescence in the solid state.…”

Organic–inorganic hybrid hexachloridostannate(IV) with 2-methylimidazo[1,5-a]pyridin-2-ium cation

“…Pursuing our research on hybrid halometalates incorporating substituted imidazo[1,5-a]pyridinium cations (Buvaylo et al, 2015;Vassilyeva et al, 2019;2020;, we attempted the synthesis of a hybrid tin mixed halide with 2-methylimidazo[1,5-a]pyridinium, L + , a product of the oxidative cyclocondensation between 2-pyridinecarbaldehyde (2-PCA), formaldehyde and CH 3 NH 2 . One necessary component of the reaction is acid, which is introduced as a hydrohalide adduct of the amine (Vassilyeva et al, 2020). Following the method of preparation used to obtain mixed-halide Zn II and Cd II tetrahalometalates (Cl/I, Br/Cl) with L + (Vassilyeva et al, 2022), SnCl 2 Á2H 2 O was reacted with the solution of L + formed in situ using 2-PCA, formaldehyde and CH 3 NH 2 ÁHBr.…”