Antonio Frontera

University of the Balearic Islands | UIB · Department of Chemistry

This perpective delves into the emerging field of matere bonds, a novel type of noncovalent interaction involving group 7 elements such as manganese, technetium, and rhenium. Matere bonds, a new...

In this study, we report the first example of acyclic (amino)(N-pyridinium)carbe-noid gold(III) complexes synthesized via a coupling reaction between 2-pyridylselenyl chloride and Au(I)-bound isonitriles. The reaction involves an initial oxidative addition of the Se-Cl moiety to Au(I), followed by the nucleophilic addition of the pyridine fragment...

The chemistry of heterocycles containing "diaza" units has been extensively studied due to their applications ranging from pharmaceuticals to advanced materials. In contrast, heterocycles incorporating heavier elements, such as Sb and Bi, remain exceedingly rare and lack straightforward synthetic methodologies. Herein, we present a comprehensive ex...

Interaction of a novel dihydroxy dibenzoazacrown (H 2 DTC) with various surfactants of different charges, for example, anionic (sodium dodecylsulfate, SDS), cationic (dodecyl trimethylammonium bromide, DTAB), cationic gemini (butane-diyl-1,4-bis(dimethylcetylammonium bromide), 16-4-16), ionic liquid (1-hexadecyl-3-methylimidazolium chloride, C 16 M...

Correction for ‘Revealing the supramolecular features of two Zn( ii ) complexes derived from a new hydrazone ligand: a combined crystallographic, theoretical and antibacterial study’ by Samit Pramanik et al. , CrystEngComm , 2023, 25 , 866–876, https://doi.org/10.1039/D2CE01445A.

Two new Co(II) coordination compounds viz. [Co(H2O)(bz)2(μ-3-Ampy)2]n (1) and [Co(4-Mebz)2(2-Ampy)2] (2) (where; bz = benzoate, 4-Mebz = 4-Methylbenzoate and Ampy = Aminopyridine) were synthesized and characterized by elemental (CHN), electronic spectroscopy, FT-IR spectroscopy, and thermogravimetric analysis (TGA). The crystal structures were dete...

Inspired by the reported crystal structure of compound 1, we aimed to synthesize and determine the structure of compound 2, where two imidazolium (H2im+) ions serve as diamagnetic countercations. Here, we report the thermal stabilities, FT–IR, visible, and RSE spectra, as well as the magnetic properties of both compounds. In these structures, µ-EDT...

In this manuscript we report the synthesis of two new zinc(II) complexes, [ZnL1(H2O)] (1) and [ZnL2(DMSO)] (2), characterized by elemental and spectral analysis {H2L1 and H2L2 are the tetradentate symmetrical salen-type, di-Schiff base ligands}. The structures have been confirmed by single-crystal X-ray diffraction analysis. The coordination polyhe...

The zwitterionic compounds [(LC)P=CS(LC/P)]⁺ (3⁺, LC=NHC, LP=PR3), featuring cationic substituents at the phosphorus and carbon atoms, are synthesized as their triflate salts at a multi‐gram scale from the reaction of lewis base adducts of CS2, namely LC/P−CS2 (4), with a combination of [(LCP)4][OTf]4 (1[OTf]4) and Ph3P. The feasibility of using 3⁺...

Herein, we describe a novel coupling between ambiphilic 2-pyridylselenyl reagents and nitriles featuring an active α-methylene group. Depending on the solvent employed, this reaction can yield two distinct types of cationic pyridinium-fused selenium-containing heterocycles, 1,3-selenazolium or 1,2,4-selenadiazolium salts, in high yields. This is in...

The crystal structures of seven metal dihalide complexes with triphenylphosphine (PPh₃) and two with tribenzylphosphine (PBz₃) have been reanalyzed. The studied complexes include [FeCl₂(PPh₃)₂], [CoCl₂(PPh₃)₂], [CoBr₂(PPh₃)₂], [NiCl₂(PPh₃)₂], [NiBr₂(PPh₃)₂], [NiI₂(PPh₃)₂], [ZnCl₂(PPh₃)₂], [NiCl₂(PBz₃)₂], and [NiBr₂(PBz₃)₂]. A detailed geometric ana...

The zwitterionic compounds [(LC)P=CS(LC/P)]+ (3+, LC = NHC, LP = PR3), featuring cationic substituents at the phosphorus and carbon atoms, are synthesized as their triflate salts at a multi‐gram scale from the reaction of Lewis base adducts of CS2, namely LC/P–CS2 (4), with a combination of [(LCP)4][OTf]4 (1[OTf]4) and Ph3P. The feasibility of usin...

Inspired by the reported crystal structure of compound 1, we aimed to synthesize and determine the structure of compound 2, where two imidazolium (H₂im⁺) ions serve as diamagnetic counter cations. Here, we report the thermal stabilities, FT-IR, visible, and RSE spectra, as well as the magnetic properties of both compounds. In these structures, µ-ED...

A dinuclear cadmium(II) complex, [Cd2(Hhqc)2(H2O)4] (H3hqc=4,8‐dihydroxyquinoline‐2‐carboxylic acid) was synthesized and characterized by single crystal X‐ray diffraction studies, elemental analyses and thermo‐gravimetric studies. The metal centers are found to be six coordinated with distorted pentagonal pyramidal geometry around them. The complex...

This study explores the synthesis, structural characterization, and examination of two nickel(II) complexes, [Ni(N3L1)2](NO3)2 (complex 1) and [Ni(N3L1)2](ClO4)2 (complex 2), using the newly synthesized organic heterocyclic chelating ligand N3L1 [4-imidazole-2,6-di(pyrazinyl)pyridine]. Through single-crystal X-ray diffraction, we have detailed the...

Complexation of the green bismuthinidene (RBi) with two equivalents of a highly fluorinated aryl iodide at low temperature allows the crystallographic identification of an unstable red species that can be regarded as an intermediate in an overall Bi(I) → Bi(III) oxidation process. Both C–I bonds are orientated toward the filled 6p orbital of bismut...

In the present work, we reported the synthesis and characterization [single crystal X-ray diffraction technique, spectroscopic, etc.] of two new Ni(II) and Zn(II) coordination compounds, viz. [Ni(2,6-PDC)2]2[Ni(en)2(H2O)2]2[Ni(en)(H2O)4]·4H2O (1) and [Zn(2,6-PDC)(Hdmpz)2] (2) (where 2,6-PDC = 2,6-pyridinedicarboxylate, en = ethylene-1,2-diamine, an...

The stability and hydrolytic behavior of squaramate esters in aqueous solutions have been investigated. The structure of squaramates and the nature of adjacent groups significantly influence their aqueous stability and reactivity towards nucleophiles. Squaramate esters, lacking or containing weakly basic neighboring group participation (NGP) substi...

In this article, we present the synthesis and characterization of three zinc(ii) complexes, [ZnII(HL¹)2] (1), [ZnII(HL²)2]·2H2O (2) and [ZnII(HL³)2] (3), with three tridentate Schiff base ligands, H2L¹, H2L², and H2L³. The structures of the complexes were confirmed by single-crystal X-ray diffraction analysis. DFT calculations were performed to gai...

Two tridentate N,N,O-donor ligands, HL¹ = 4-chloro-2-(((2-(methylamino)ethyl)amino)methyl)phenol and HL² = 4-chloro-2-(((2-(dimethylamino)ethyl)amino)methyl)phenol, have been used to synthesize phenolate-bridged dinuclear complexes [Zn2(L¹)2Cl2] (1) and [Zn2(L²)2(N3)2] (2). Single-crystal X-ray diffraction analysis confirmed their structures. Both...

A novel nanosized porous supramolecular nonanuclear complex [Pb9(HL)12Cl2(ClO4)](ClO4)3·15H2O·a(solvent) (1·15H2O·a(solvent)) is reported that was synthesized by electrochemical oxidation of a Pb anode under the ambient conditions in a CH3CN:MeOH solution of N′-phenyl(pyridin-2-yl)methylene-N-phenylthiosemicarbazide (H2L), containing [N(CH3)4]ClO4...

The −N⁺(CH3)3 residue is present in acetylcholine (ACh) and in many of its analogues which are used as selective ACh agonist or antagonists for human therapy. The X‐ray structures of four ACh derivatives show the presence of short and linear contacts between the C atoms of −N⁺(CH3)3 groups and lone pair possessing atoms. These contacts can be ratio...

A pentadentate diamide ligand, N,N′‐di(pyridine‐2‐yl)pyridine‐2,6‐dicarboxamide (L¹H2) and its tetranuclear Cu(II) complex [Cu4(L¹)2(μ3‐OH)2(H2O)3(ClO4)](ClO4) ⋅ H2O are reported. X‐ray crystal structure of the complex reveals that it has an open‐book type architecture. Two central copper atoms are connected to each other by two hydroxo bridges. Ea...

The objective of this study was to create artificial enzymes that capitalize on pnictogen bonding, a σ‐hole interaction that is essentially absent in biocatalysis. For this purpose, stibine catalysts were equipped with a biotin derivative and combined with streptavidin mutants to identify an efficient transfer hydrogenation catalyst for the reducti...

The crystal structure of [Co(H2O)6][Co(SMX)3]2 complex (SMX = sulfamethoxazole), hereafter CoSMXW, has been solved by X-ray diffraction methods. The complex CoSMXW was characterized by Infrared (IR), Raman, and UV-Vis spectroscopies. A comparison with the analogous Mn(II) complex, [Mn(H2O)6][Mn(SMX)3]2 (CSD refcode AJIFUW), indicates 3D isostructur...

This work synthesized two Hg complexes (1-2) using a LO-rich ligand (LO-rich =LO-VAN/LET-VAN) in CH3OH and CH3OH/DCM media. Complex 1 is discrete [(HgCl2)3LO-VAN], while 2 is the coordination polymer (CP) [HgCl2LET-VAN] n. The complexes were characterized using spectroscopy, SCXRD, HRMS, PXRD, SEM-EDX, and XPS study. The X-ray structure revealed th...

A microwave‐assisted synthesis of 7‐amino‐1,2,4‐triazolo[1,5‐a][1,3,5]triazine‐2‐propanamides was developed using a three‐component, catalyst‐free reaction of cyanamide and trimethyl orthoformate with 3‐(5‐amino‐1H‐1,2,4‐triazol‐3‐yl)propanamides (3). The reaction tolerated structurally diverse substrates and proceeded chemo‐ and regio‐selectively,...

A series of novel benzoyl and acetyl pyrazine-2-carbohydrazonamide hybrid derivatives, namely N’-benzoylpyrazine-2-carbohydrazonamide (1), N’-(4-methylbenzoyl)pyrazine-2-carbohydrazonamide (2), N’-(2-phenylacetyl)pyrazine-2-carbohydrazonamide (3) and N’-(2-(1H-indol-3-yl)acetyl)pyrazine-2-carbohydrazonamide (4), were readily obtained using a metall...

Herein, we have reported the synthesis and characterization [single crystal X-ray diffraction technique, spectroscopic etc.] of two new Ni(II) and Zn(II) coordination compounds viz. [Ni(2,6-PDC)2]2[Ni(en)2(H2O)2]2[Ni(en)(H2O)4]·4H2O (1) and [Zn(2,6-PDC)(Hdmpz)2] (2) (where, 2,6-PDC = 2,6-pyridinedicarboxylate, en = ethylene-1,2-diamine, Hdmpz = 3,5...

Herein we have evidenced the formation of favorable π‐hole Br⋅⋅⋅metal noncovalent interactions (NCIs) involving elements from groups 9, 11 and 12. More in detail, M (M=Co²⁺, Ni²⁺, Cu²⁺ and Zn²⁺) containing porphyrins have been synthesized and their supramolecular assemblies structurally characterized by means of single crystal X‐ray diffraction and...

Herein, we report the synthesis of a Pb(II) based three-dimensional coordination polymer (3D CP), [Pb(DCTP)]n (1) [H2DCTP = 2,5-dichloroterephthalic acid] with unprecedented topology, which shows photomechanical effect wherein crystals show jumping upon UV irradiation. The Pb(II) CP forms type II Cl···Cl interaction which weakens further in 2 and 3...

Cis‐5,15‐bis(3,5‐trifluoromethylphenyl)calix[4]pyrrole (1) forms stable 1/1 complexes with linear anions such as N3⁻, SCN⁻ and NCO‐ with the highest affinity for NCO⁻ anion in acetonitrile solution. Crystallization of receptor 1 with TBASCN and (TMA)2SO4 resulted in the formation of dimeric capsular assembly, {(TMA)2[12 ⋅ (SCN)2]}, in which two thi...

In X‐ray structures of the isomorphic mer‐[IrX3(THT)(CNXyl)2] (X=Cl 1, Br 2; THT=tetrahydrothiophene; Xyl=2,6‐Me2C6H3−) complexes, we revealed short intermolecular contacts between the C‐atom of an isocyanide methyl group and halide ligands of another molecule. Geometrical consideration of the X‐ray data and analysis of appropriate DFT studies allo...

(ClImDipp)P–P(Dipp)· (1·), a rare example of a neutral, mixed substituted diphosphene radical, has been prepared by reduction of ( Cl Im Dipp )PP(Dipp)[OTf] ( 2 [OTf]) and ( Cl Im Dipp )PP(Cl)(Dipp) ( 3 ) with cobaltocene (CoCp 2 ) ( Cl Im Dipp = 4,5-dichloro-1,3-bis(1,3-diisopropylphenyl)-imidazol-2-yl, Dipp...

The objective of this study was to create artificial enzymes that capitalize on pnictogen bonding, a s‐hole interaction that is essentially absent in biocatalysis. For this purpose, stibine catalysts were equipped with a biotin derivative and combined with streptavidin mutants to identify an efficient transfer hydrogenation catalyst for the reducti...

The first example of N-confused strapped calix[4]pyrrole 5 is presented. Structural integrity of 5 and its regular isomer 4 was unambiguously confirmed by the single crystal X-ray diffraction analysis. Anion binding studies using 1H NMR titration carried out in CDCl3 revealed little but detectable tendency of 5 to interact with anion. On the other...

With an objective to gain insights into the modulation of reduction potential of Ni(II/I) couple, we have synthesized two mononuclear nickel(II) complexes, NiL en (H 2 L en = N,N'-bis(3-methoxysalicylidene)-1,2-diamino-2-methylpropane) and NiL pn (H 2 L pn = N,N'-bis(3-methoxysalicylidene)-1,3-diamino-2,2-dimethylpropane) of two N 2 O 4 donor ligan...

Herein we have evidenced the formation of favorable π‐hole Br···metal noncovalent interactions (NCIs) involving elements from groups 9, 11 and 12. More in detail, M (M = Co2+, Ni2+, Cu2+ and Zn2+) containing porphyrins have been synthesized and their supramolecular assemblies structurally characterized by means of single crystal X‐ray diffraction a...

The structure-directing “key-to-lock” interaction of double σ-(IIII)-hole donating iodonium cations with the O-flanked pseudo-lacune rims of [β-Mo8O26]⁴⁻ gives halogen-bonded iodonium-beta-octamolybate supramolecular associates. In the occurrence of their tetragonal pyramidal motifs, deep and broad σ-(IIII)-holes of a cation recognize the molybdate...

The use of organic ligands for the generation of supramolecular architectures exhibiting interesting structural properties in crystal engineering have garnered significant attention. In this context, the current work highlights the use of 1-(4-(4-bromophenyl)piperazin-1-yl)-2-chloroethan-1-one (3) as a valuable synthon for evaluating the conspicuou...

The chemistry of light dipnictenes has been widely investigated in the last century with remarkable achievements especially for azobenzene derivatives. In contrast, distibenes and dibismuthenes are relatively rare and show very limited reactivity. Herein, we have designed a protocol using visible light to enhance the reactivity of heavy dipnictenes...

The co-crystallization of S-(CF 3 )-dibenzothiophenium (“Umemoto” – abbreviated Ume) cations and polycyanometalates with different coordination geometries yields a large structural variety of supramolecular assemblies. In case of [Ume ⁺ ] 2 [Ni(CN) 4 ] ²⁻ ∙CH 2 Cl 2 all four cyanide...

In this study, Fe3O4 nanoparticles (FeNPs) decorated with halogenated perylene diimides (PDIs) have been used for capturing VOCs (volatile organic compounds) through noncovalent binding. Concretely, we have used tetrachlorinated/brominated PDIs as well as a nonhalogenated PDI as a reference system. On the other hand, methanol, ethanol, propanol, an...

The synthesis and XRD characterization of two new 1,4-benzoxazine derivatives (3a-5a) namely ethyl‐6‐nitro‐3a‐(p‐tolylamino)‐1,2,3,3a‐tetrahydrobenzo[b]cyclopenta[e][1,4]oxa-zine‐9a(9H)‐carboxylate (3a) and methyl-6,10b-dimethyl-5a,6,10b,11-tetrahydrobenzo[5,6][1,4]oxazino[2,3-b]indole-2-carboxylate (5a) are reported herein. In both compounds it is...