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Herein, we disclose the first report on gold‐catalyzed C(sp2)‐CN cross‐coupling reaction by employing a ligand‐enabled Au(I)/Au(III) redox catalysis. This transformation utilizes acetone cyanohydrin as a nucleophilic cyanide source to convert simple aryl and alkenyl iodides into the corresponding nitriles. Combined experimental and computational studies highlighted the crucial role of cationic silver salts in activating the stable (P,N)‐AuCN complex towards the oxidative addition of aryl iodides to subsequently generate key aryl‐Au(III) cyanide complexes. [ABSTRACT FROM AUTHOR]

A bisphosphirane‐fused anthracene (5) was prepared by treatment of a sterically encumbered amino phosphorus dichloride (3) with MgA ⋅ THF3 (A=anthracene). X‐ray diffraction analysis revealed a pentacyclic framework consisting of 5 with two phosphirane rings fused to the anthracene in a trans‐fashion. Compound 5 has been shown to be an efficient phosphinidene synthon, readily liberating two transient phosphinidene units for subsequent downstream bond activation via the reductive elimination of anthracene under mild conditions. The formal oxidative addition of H2 and E−H (E=Si, N, P) bonds by the liberated phosphinidene provided diphosphine and substituted phosphines. Furthermore, phosphinidene transfer to alkenes and alkynes smoothly yielded the corresponding phosphiranes and phosphirenes. The mechanism of the H2 activation by 5 was investigated by density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

We report a study of solvent effects on the rate, selectivity, and mechanism of (hetero)aryl (pseudo)halide oxidative addition to Pd(PCy3)2 as an exemplar of L2Pd(0) species. First, 2‐chloro‐3‐aminopyridine is observed to undergo faster oxidative addition in toluene compared to more polar solvents, which is not consistent with the trend we observe with many other 2‐halopyridines. We attribute this to solvent basicity hydrogen bonding between solvent and substrate. Greater hydrogen bond donation from the substrate leads to a more electron‐rich aromatic system, and therefore slower oxidative addition. We demonstrate how this affects rate and site‐selectivity for hydrogen bond donating substrates. Second, electron‐deficient multihalogenated pyridines exhibit improved site‐selectivity in polar solvents, which we attribute to different C−X sites undergoing oxidative addition by two different mechanisms. The C−X site that favours the more polar nucleophilic displacement transition state is preferred over the site that favours a less‐polar 3‐centered transition state. Finally, (hetero)aryl triflates consistently undergo faster oxidative addition in more polar solvents, which we attribute to highly polar nucleophilic displacement transition states. This leads to improved site‐selectivity for C−OTf oxidative addition, even in the presence of highly reactive 2‐pyridyl halides. [ABSTRACT FROM AUTHOR]

Quantitative molecular structure‐reactivity models are useful for generating predictions to guide synthesis design, and in formulating and testing mechanistic hypotheses. We report an expanded multivariate linear regression (MLR) model for the rate of (hetero)aryl (pseudo)halide oxidative addition to L2Pd(0), here exemplified by Pd(PCy3)2. This builds on a prior model from our group, with additional substrate classes (aryl chlorides and iodides) and reaction solvents (THF, toluene, THF/DMF mixture). Overall solvent effects across the entire substrate set are minimal under these conditions, enabling a unified MLR model without introduction of new molecular descriptors beyond the original five. Examining the mechanistic origin of the two molecular electrostatic potential (ESP) descriptors led to generation of a simpler, four descriptor model that is suitable for aryl halides, but not for 2‐halopyridines. Using this model we identified a mechanistic outlier, 2‐pyridyl triflate, which undergoes a nucleophilic displacement oxidative addition that does not involve the adjacent nitrogen atom. Finally, we discuss the relationship between C−X bond strength and oxidative addition rates, and compare the intrinsic bond strength index (IBSI) to bond dissociation enthalpy (BDE) as a bond strength descriptor. [ABSTRACT FROM AUTHOR]

ABSTRACT Herein, pyrazinamide (L1) was used as a powerful ligand to promote a CuSO4‐catalyzed reaction between aryl halides and imidazole (HID) under mild conditions, generating various N‐arylation products in good to excellent yields. The findings indicate that CuSO4 was reduced and coordinated with L1 to form [CuIL1], which activated ArX to produce [ArCuIL1X] through oxidative addition. This intermediate subsequently underwent reductive elimination to form N‐arylation products, with [ArCuILID] being generated from a reaction between [ArCuIL1X] and HID. This method was successfully extended to the synthesis of 2‐phenylindole and pyrrolo[1,2‐a]quinoxaline under mild conditions. The method significantly enhances the efficiency and cost effectiveness of C‐N coupling reaction. [ABSTRACT FROM AUTHOR]

Aryl fluorosulfates of varying complexities have been used in amination reactions in water using a new Pd oxidative addition complex (OAC‐1) developed specifically to match the needs of the fine chemicals industry, not only in terms of functional group tolerance, but also reflecting time considerations associated with these important C−N couplings. Also especially noteworthy is that they replace both PFAS‐related triflates and nonaflates, which are today out of favor due to recent government regulations. The new complex based on the BippyPhos ligand is used at low loadings and under aqueous micellar conditions. Moreover, it is easily prepared and stable to long term storage. DFT calculations on the OAC precatalyst compare well with the X‐ray structure of the crystals with π‐complexation to the aromatic system of the ligand and also confirm the NMR data showing a mixture of conformers in solution that differ from the X‐ray structure in rotation of the phenyl and t‐butyl ligand substituents. An extensive variety of coupling partners, including pharmaceutically relevant APIs, readily participate under mild and environmentally responsible reaction conditions. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculation has been used to reveal palladium‐catalyzed mode of diaziridinone ring activation. Our theoretical studies found that oxidative addition of di‐tert‐butyldiaziridinone to Pd(II) can give a high valent Pd(IV) intermediate, along with the cleavage of N─N bond in di‐tert‐butyldiaziridinone through a concerted three‐membered‐cyclic transition state. Subsequent transformations via reductive elimination and β‐N elimination give the desired indolo[3,2‐b]indole product. The competitive activation modes such as metathesis and migratory insertion can be excluded in our selected model reaction. The rate‐determining step of this reaction is the oxidative addition of di‐tert‐butyldiaziridinone step. Distortion‐interaction analysis was conducted to reveal that the oxidative addition mode of di‐tert‐butyldiaziridinone is superior to the metathesis mode due to the lower interaction energy. [ABSTRACT FROM AUTHOR]

For square-planar late transition metal pyridine, diimine (Rh, Ir) complexes with hydro-xido, methoxido, and thiolato ligands. We could previously establish sizable metal-O- and S π-bonding interactions. Herein, we report the hydrogenation studies of iridium hydroxido and methoxido complexes, which quantitatively lead to the trihydride compound and water/methanol. The iridium trihydride displays a highly fluctional structure with scrambling hydrogen atoms, which can be described as a dihydrogen hydride system based on NMR and DFT investigations. This contrasts the iridium sulfur compounds, which are not reacting with dihydrogen. According to DFT and LNO-CCSD(T) calculations, hydrogenation of the methoxido complex proceeds by a two-step mechanism, i.e., an oxidative addition step of H2 to an Ir(III) dihydride intermediate with consecutive reductive O-H elimination of methanol. Based on PNO-CCSD(T) calculations, the reactivity difference between the O- and S-donors can be traced to the stronger H-O bonds in the water/methanol products compared to the S-H bonds in the sulphur congeners, which serves as a driving force for hydrogenation. [ABSTRACT FROM AUTHOR]

The ubiquitous nature of amines in drug compounds, bioactive molecules and natural products has fueled intense interest in their synthesis. Herein, we introduce a nickel‐catalyzed enantioconvergent allenylic amination of methanol‐activated allenols. This protocol affords a diverse array of functionalized allenylic amines in high yields and with excellent enantioselectivities. The synthetic potential of this method is demonstrated by employing bioactive amines as nucleophiles and conducting gram‐scale reactions. Furthermore, mechanistic investigations and DFT calculations elucidate the role of methanol as an activator in the nickel‐catalyzed reaction, facilitating the oxidative addition of the C−O bond of allenols through hydrogen‐bonding interactions. The remarkable outcomes arise from a rapid racemization of allenols enabled by the nickel catalyst and from highly enantioselective dynamic kinetic asymmetric transformation of η3‐alkadienylnickel intermediates. [ABSTRACT FROM AUTHOR]

Reforming tar molecules into smaller gaseous molecules has been a critical challenge for biomass energy utilization. Hematite (α-Fe2O3) has been demonstrated as an effective catalyst for the catalytic reforming of tar, nevertheless, the detailed mechanism of α-Fe2O3 catalyzed tar reforming remains unclear. In this work, we apply the density functional theory method to investigate this problem. Specifically, we study both (0001) and (01 2) surface structures of α-Fe2O3 and then use the structures to investigate the adsorption and C–C bond cleavage of benzene on these surfaces. Our results show that the dominant interactions between benzene and a single Fe-terminated (0001) surface are van der Waals forces, yet benzene could be chemisorbed on the Fe and O co-exposed (01 2) surface via strong C–O interactions. As a result, the (0001) surface is not active towards benzene cleavage, whereas the (01 2) surface can promote the aromatic C–C bond breaking. Furthermore, our calculations indicate that chain-like alkene species and carbonyl species are the two types of potential products that form after the C–C bond cleavage of benzene on the α-Fe2O3 (01 2) surface, with the activation energy of 1.78 eV and 2.62 eV, respectively. In summary, we reveal the importance of co-adsorption on both Fe and O centers and oxidative addition on C–C bond cleavage of aromatic compounds on the α-Fe2O3 surface, which provides novel insights into the mechanisms of tar cracking on oxide catalysts. [ABSTRACT FROM AUTHOR]

Cross‐electrophile coupling (XEC) between aryl halides and alkyl halides is a streamlined approach for C(sp2)−C(sp3) bond construction, which is highly valuable in medicinal chemistry. Based on a key NiII aryl amido intermediate, we developed a highly selective and scalable Ni‐catalyzed electrochemical XEC reaction between (hetero)aryl halides and primary and secondary alkyl halides. Experimental and computational mechanistic studies indicate that an amine secondary ligand slows down the oxidative addition process of the Ni‐polypyridine catalyst to the aryl bromide and a NiII aryl amido intermediate is formed in situ during the reaction process. The relatively slow oxidative addition is beneficial for enhancing the selectivity of the XEC reaction. The NiII aryl amido intermediate stabilizes the NiII–aryl species to prevent the aryl–aryl homo‐coupling side reactions and acts as a catalyst to activate the alkyl bromide substrates. This electrosynthesis system provides a facile, practical, and scalable platform for the formation of (hetero)aryl–alkyl bonds using standard Ni catalysts under mild conditions. The mechanistic insights from this work could serve as a great foundation for future studies on Ni‐catalyzed cross‐couplings. [ABSTRACT FROM AUTHOR]

The mechanism of an iron‐catalyzed C—H alkenylation of pivalophenone derivatives with unsymmetric internal alkynes is investigated in details by means of density functional theory calculations. It is shown that the reaction begins with two consecutive ligand exchanges, followed by a fast and reversible oxidative addition C—H activation step. Next, an alkyne insertion into the Fe—H bond, two isomerization steps, and a reductive elimination afford the final product. The reductive elimination is the turnover‐limiting step of the process, and also determines the regiochemical outcome of the reaction. The origin of the regioselectivity is proposed to be the steric repulsion between the bulky trimethylsilyl group and the aromatic fragment in the reductive elimination step leading to the not observed regioisomer. [ABSTRACT FROM AUTHOR]

Chiral allylic alcohols are highly prized in synthetic chemistry due to their versatile reactivity stemming from both alkenyl and hydroxyl functionalities. While the Nozaki–Hiyama–Kishi (NHK) reaction is a widely used method for the synthesis of allylic alcohols, it suffers from drawbacks such as the use of toxic chromium salts, high amounts of metal reductants, and poor enantiocontrol. To address these limitations, we present a novel approach involving a metallaphotoredox‐catalyzed asymmetric NHK reaction for the production of chiral allylic alcohols. This method marries alkenyl (pseudo)halides with aldehydes, leveraging a synergistic blend of a chiral nickel catalyst and a photocatalyst. This innovative technique enables both oxidative addition and insertion just using nickel, diverging significantly from the conventional NHK reaction pathway mediated by nickel and chromium salts. The adoption of this methodology holds immense promise for crafting a spectrum of intricate compounds, particularly those of significance in pharmaceuticals. Detailed experimental investigations have shed light on the metallaphotoredox process, further enhancing our understanding and enabling further advancements. [ABSTRACT FROM AUTHOR]

The mechanistic details of the asymmetric Ni‐catalyzed reductive cyclization/carboxylation of alkenes with CO2 have been revisited using DFT methods. Emphasis was put on the enantioselectivity and the mechanistic role of Lewis acid additives and in situ formed salts. Our results show that oxidative addition of the substrate is rate‐limiting, with the formed Ni(II)‐aryl intermediate preferring a triplet spin state. After reduction to Ni(I), enantioselective cyclization of the substrate occurs, followed by inner sphere carboxylation. Our proposed mechanism reproduces the experimentally observed enantiomeric excess and identifies critical C−H/O and C−H/N interactions that affect the selectivity. Further, our results highlight the beneficial effect of Lewis acids on CO2 insertion and suggest that in situ formed salts influence if the 5‐exo or 6‐endo product will be formed. [ABSTRACT FROM AUTHOR]

The adducts 2M,R of general formula trans‐[(L)M{R2P(CH2)2PR2}2{N2B(C6F5)3}] (L=ø or N2, M=Mo or W, R=Et or Ph), formed from Lewis acid‐base pairing of B(C6F5)3 to a dinitrogen ligand of zero‐valent group 6 bis(phosphine) complexes trans‐[M{R2P(CH2)2PR2}2(N2)2] are shown to react with dihydrogen to afford hepta‐coordinated bis(hydride) complexes [M(H)2{R2P(CH2)2PR2}{N2B(C6F5)3}] 3M,R which feature the rare ability to activate both dinitrogen and dihydrogen at a single metal center, except in the case where M=Mo and R=Ph for which fast precipitation of insoluble [Mo(H)4(dppe)2] (dppe=1,2‐bis(diphenylphosphino)ethane) occurs. The frustrated Lewis pair (FLP)‐related reactivity of the B−N linkage in compounds 3W,R was explored and led to distal N functionalization without involvement of the hydride ligands. It is shown in one example that the resulting bis(hydride) diazenido compounds may also be obtained through a sequence involving first FLP‐type N‐functionalization followed by oxidative addition of H2. Those oily compounds were found to have limited stability in solution or in their isolated states. Finally, treatment of 3W,Et with the Lewis base N,N‐dimethylaminopyridine (DMAP) affords the simple but unknown bis(hydride)‐dinitrogen species [W(H)2(depe)2(N2)] 11Et (depe=1,2‐bis(diethylphosphino)ethane) which direct, selective formation from trans‐[W(N2)2(depe)2] is not possible. [ABSTRACT FROM AUTHOR]

Effects of different conditions on the reaction of alkenes with phenyl[(trifluoromethanesulfonyl)-imino]-λ3-iodane (PhI=NTf, 1) have been studied. The reaction of PhI=NTf with styrenes in the presence of copper(I) chloride led to the formation of substituted aziridine and bis-trifluorometanesulfonamido derivatives at different ratios. When silver nitrate was used as additive in the same reaction, 1-phenyl-2-(trifluoro-methanesulfonamido)ethyl nitrate was formed. Isomeric amidines were obtained from camphene as substrate in the presence of different activating additives and an oxidant. Potential biological activity of the synthesized compounds was predicted using PASS Online software. [ABSTRACT FROM AUTHOR]

The chemistry of transition‐metal (TM) complexes with monoanionic bidentate (κ2‐L,Si) silyl ligands has considerably grown in recent years. This work summarizes the advances in the chemistry of TM‐(κ2‐L,Si) complexes (L=N‐heterocycle, phosphine, N‐heterocyclic carbene, thioether, ester, silylether or tetrylene). The most common synthetic method has been the oxidative addition of the Si−H bond to the metal center assisted by the coordination of L. The metal silicon bond distances in TM‐(κ2‐L,Si) complexes are in the range of metal‐silyl bond distances. TM‐(κ2‐L,Si) complexes have proven to be effective catalysts for hydrosilylation and/or hydrogenation of unsaturated molecules among other processes. [ABSTRACT FROM AUTHOR]

Pd‐catalyzed stereoselective glycosylations using unsaturated sugar derivatives, glycals, have been successfully achieved in recent years. This review focuses on approaches to control the stereoselectivities of glycosides via π‐allyl intermediates that mimic the Tsuji–Trost asymmetric allylic alkylation reactions, enabling stereoselectivity control through rational design. In the reaction process, zwitterionic Pd‐π‐allyl complexes, formed after the oxidative addition and decarboxylation, play a crucial role in increasing reactivities and enhancing the stereoselectivities of α‐ and β‐glycosides. We summarized recently developed Tsuji–Trost type glycosylations using 3,4‐carbonate galactals, featuring high efficiency, exclusive stereoselectivities, and a broad reaction scope including O‐, N‐, S‐, and C‐glycosylations. [ABSTRACT FROM AUTHOR]

Using visible light conditions, we have developed a green protocol to prepare copper oxide‐doped graphitic carbon nitride (Cu2O@g‐C3N4) photocatalysts with varied ratios of g‐C3N4 nanosheets to copper oxide‐dopant (0.1 %, 0.5 %, 0.7 %, and 5 % respectively) and characterized through various physicochemical techniques. These photo‐responsive catalysts were used for the 1,4 radical oxidative addition of trans crotonaldehyde into β‐hydroxybutyric acid (BA) as a major product, utilizing 30 % hydrogen peroxide as an oxidant and a white LED (Light Emitting Diode) source. Under the innoculous eco‐friendly stipulations, Cu2O@g‐C3N4 (5 %) exclusively promoted the aforementioned reaction leading to 99.85 % trans crotonaldehyde conversion with 66.57 %, 24.1 %, and 9.1 % selectivity for β‐hydroxybutyric acid, crotonic acid and subsequent radical synthesis, respectively. [ABSTRACT FROM AUTHOR]

The synthesis of three novel [C,N,N′] Pt(IV) cyclometallated compounds containing hydroxo, dichloroacetato or trifluoroacetato axial ligands is reported. Compound [PtCl(OH)2{(CH3)2N(CH2)2N＝CH(4-FC6H3)}] (3) was prepared by the oxidative addition of hydrogen peroxide to [C,N,N′] Pt(II) cyclometallated compound [PtCl{(CH3)2N(CH2)2N＝CH(4-FC6H3)}] (1) and further the reaction of compound 3 with dichloroacetate or trifluoroacetate anhydrides led to the formation of the corresponding compounds [PtCl(CHCl2COO)2{(CH3)2N(CH2)2N＝CH(4-FC6H3)}] (4) and [PtCl(CF3COO)2{(CH3)2N(CH2)2N＝CH(4-FC6H3)}] (5). The properties of the new compounds along with those of the compound [PtCl3{(CH3)2N(CH2)2N＝CH(4-FC6H3)}] (2), including stability in aqueous media, reduction potential using cyclic voltammetry, cytotoxic activity against the HCT116 CRC cell line, DNA interaction, topoisomerase I and cathepsin inhibition, and computational studies involving reduction of the Pt(IV) compounds and molecular docking studies, are presented. Interestingly, the antiproliferative activity of these compounds against the HCT116 CRC cell line, which is in all cases higher than that of cisplatin, follows the same trend as the reduction potentials so that the most easily reduced compound 2 is the most potent. In contrast, according to the electrophoretic mobility and molecular docking studies, the efficacy of these compounds in binding to DNA is not related to their cytotoxicity. The most active compound 2 does not modify the DNA electrophoretic mobility while the less potent compound 3 is the most efficient in binding to DNA. Although compounds 2 and 3 have only a slight effect on cell cycle distribution and apoptosis induction, generation of ROS to a higher extent for the most easily reduced compound 2 was observed. [ABSTRACT FROM AUTHOR]

Mono or bis(tetrazole–thiolato) Pd(II) or Pt(II) complexes were obtained from the reactions of dialkyl Pd(II) or Pt(II) complexes with organic tetrazole–thiones (1-aryl- or 1-alkyl-1H-tetrazole-5-thiones) via deprotonation. In contrast, equimolar reactions of zerovalent Pt(0) or Pd(0) complexes with organic tetrazole–thiones afforded hydrido or bis(tetrazole–thiolato) Pt(II) and Pd(II) complexes, and cyclometallated Pt(II) or Pd(II) complexes bearing a tetrazole–thiolato moiety via oxidative addition, depending on the organic substituents on the tetrazole–thiones. In particular, variable (time and temperature)-dependent 1H-NMR spectra of the hydrido Pt(II) tetrazole–thiolates reveal an upfield shift of the hydride signal, suggesting N,S-coordination behavior of the tetrazole–thiolato ligand. Additionally, the N-CH2 signal corresponds to the six-membered ring of platinacycle or palladacycle exhibiting geminal coupling with multiple protons and PR3 ligands; these coupling values were further determined using 1H{31P} experiments. Finally, treatment of the alkyl Pd(II) tetrazole–thiolate or Pd(II) bis(tetrazole–thiolates) with organic tert-butyl isocyanide, thiophenol, and organic halides caused the selective insertion of the isocyanide into the Pd–C bond or deprotonation to afford a Pd(II) disulfide complex and substitution to afford new organic tetrazolyl sulfides. [ABSTRACT FROM AUTHOR]

Two‐electron oxidative addition is one of the most important elementary reactions for d‐block transition metals but it is uncommon for f‐block elements. Here, we report the first examples of intermolecular oxidative addition of E−H (E=C, N) bonds to uranium(II) centers. The transient U(II) species was formed in‐situ by reducing a heterometallic cluster featuring U(IV)‐Pd(0) bonds with potassium‐graphite (KC8). Oxidative addition of C−H or N−H bonds to the U(II) centers was observed when this transient U(II) species was treated with benzene, carbazole or 1‐adamantylamine, respectively. The U(II) centers could also react with tetracene, biphenylene or N2O, leading to the formation of arene reduced U(IV) products and uranyl(VI) species via two‐ or four‐electron processes. This study demonstrates that the intermolecular two‐electron oxidative addition reactions are viable for actinide elements. [ABSTRACT FROM AUTHOR]

The ultrasonic induced oxidative addition reaction of C60 fullerene to tris(hydroxymethyl)-aminomethane in a toluene—DMF solvent mixture in the presence of LiOH and Pb(OAc)4 at room temperature in an aerobic environment gave 47% yield of the C60 fullerene monoadduct containing in its structure a morpholine fragment annulated to the [60]fullerene core. [ABSTRACT FROM AUTHOR]

The energy profile for vinyl iodide (RI) electrophile C(sp2)–C(sp2) homocoupling catalyzed by platinum(II) iodo complexes has been theoretically evaluated by the DFT method using the hybrid meta exchange-correlation functional M06 and the LANL2DZ basis set in the Gaussian09 software package. The reaction mechanism proposed earlier on the basis of experimental data was confirmed, consisting of the sequence of the following steps: RI oxidative addition to PtII to form the intermediate compound RPtIV— reduction of the latter by iodide ions into RPtII—RI oxidative addition to form R2PtIV—reductive elimination to yield the final butadiene-1,3. The highest activation barrier was found for the oxidative addition of the second vinyl iodide molecule, which is consistent with the experimental fact that the overall catalytic reaction rate is limited by just this step. [ABSTRACT FROM AUTHOR]

Recent advances in the isolation of tamed bismuth radicals and the selective in situ generation of highly reactive bismuth radicals have set the stage for the application of these compounds in organic and organometallic synthesis and catalysis. Here, we provide a summary of the methodological approaches in the field. Important strategies for accessing bismuth radical species are presented and key examples of their applications in organic synthesis are outlined, highlighting how this class of compounds has emerged as new set of valuable tools for synthetic practitioners. 1 Introduction 2 Generation of Bismuth Radical Species by Homolysis 2.1 Temperature-Induced Homolysis 2.2 Light-Induced Homolysis 2.3 Light-/Temperature-Induced Bi–C Homolysis of Polar Oxidative Addition Complexes 3 Applications of Bismuth-Centered Radical Species in Organic Synthesis 3.1 Bismuth-Catalyzed Cycloisomerization of Iodo Olefins 3.2 Controlled Radical Polymerization Reactions 3.3 Bismuth-Promoted Pn–Pn and C–S Coupling 3.4 Bismuth-Catalyzed Dehydrocoupling of Silanes with TEMPO 3.5 Bismuth-Catalyzed C–N Coupling with Redox-Active Electrophiles 3.6 Bismuth-Catalyzed Giese-Type Coupling Reactions 3.7 Oxidative Addition of Aryl Electrophiles to Photoactive Bismuthinidenes 4 Conclusions [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogenation of 1‐octene as non‐activated model substrate with neutral water as H‐donor is reported, using [(tBuPCP)Ir(H)(Cl)] (1) as the catalyst, to form octane with high faradaic efficiency (FE) of 96 % and a kobs of 87 s−1. Cyclic voltammetry with 1 revealed that two subsequent reductions trigger the elimination of Cl− and afford the highly reactive anionic Ir(I) hydride complex [(tBuPCP)Ir(H)]− (2), a previously merely proposed intermediate for which we now report first experimental data by mass spectrometry. In absence of alkene, the stoichiometric electrolysis of 1 in THF with water selectively affords the Ir(III) dihydride complex [(tBuPCP)Ir(H)2] (3) in 88 % FE from the reaction of 2 with H2O. Complex 3 then hydrogenates the alkene in classical fashion. The presented electro‐hydrogenation works with extremely high FE, because the iridium hydrides are water stable, which prevents H2 formation. Even in strongly alkaline conditions (Bu4NOH added), the electro‐hydrogenation of 1‐octene with 1 also proceeds cleanly (89 % FE), suggesting a highly robust process that may rely on H2O activation, reminiscent to transfer hydrogenation pathways, instead of classical H+ reduction. DFT calculations confirmed oxidative addition of H2O as a key step in this context. [ABSTRACT FROM AUTHOR]

The different structures and behaviors of UO2+x observed in crystallographic and local structure measurements were examined by extended X-ray absorption fine structure (EXAFS) measurements of pristine UO2.0, p+ and He2+ irradiated UO2.0, and, at multiple temperatures, bulk U4O9 and U3O7 and thin film U4O9-δ on an epitaxial substrate. The disorder caused by irradiation is mostly limited to increased widths of the existing U-O/U pair distributions, with any new neighbor shells being minor. As has been previously reported, the disorder caused by oxidative addition to U4O9 and U3O7 is much more extensive, resulting in multisite U-O distributions and greater reduction of the U-U amplitude with different distributions in bulk and thin-film U4O9. This includes the significant spectral feature near R = 1.2 Å for all U4O9 and U3O7 samples fit with a U-oxo type moiety with a U-O distance around 1.7 Å. In addition to indicating that these anomalies only occur in mixed valence materials, this work confirms the continuous rearrangement of the U-O distributions from 10 to 250 K. Although these variations of the structure are not observed in crystallography, their prominence in the EXAFS indicates that the dynamic structure underlying these effects is an essential factor of these materials. [ABSTRACT FROM AUTHOR]

This article explores the synthesis of α,β-unsaturated carbonyl compounds, which have applications in pharmacology and materials science. It discusses various methods for synthesizing these compounds, with a focus on the use of earth-abundant metals like iron and cobalt as catalysts. The authors explain the mechanisms involved in these reactions and highlight the advantages of using earth-abundant metals. While these methods have been used in the synthesis of pharmaceuticals and bioactive molecules, there are still challenges to overcome, and more research is needed to develop more efficient and environmentally friendly catalytic systems. [Extracted from the article]

An Artificial Metalloenzyme (ArM) built employing the streptavidin‐biotin technology has been used for the enantioselective synthesis of binaphthyls by means of asymmetric Suzuki‐Miyaura cross‐coupling reactions. Despite its success, it remains a challenge to understand how the length of the biotin cofactors or the introduction of mutations to streptavidin leads the preferential synthesis of one atropisomer over the other. In this study, we apply an integrated computational modeling approach, including DFT calculations, protein‐ligand dockings and molecular dynamics to rationalize the impact of mutations and length of the biotion cofactor on the enantioselectivities of the biaryl product. The results unravel that the enantiomeric differences found experimentally can be rationalized by the disposition of the first intermediate, coming from the oxidative addition step, and the entrance of the second substrate. The work also showcases the difficulties facing to control the enantioselection when engineering ArM to catalyze enantioselective Suzuki‐Miyaura couplings and how the combination of DFT calculations, molecular dockings and MD simulations can be used to rationalize artificial metalloenzymes. [ABSTRACT FROM AUTHOR]

Ruthenium complexes with facially coordinating tripodal phosphine ligands are privileged catalysts for a broad range of (de-)hydrogenation-based transformations. Among these, C–O bond hydrogenolysis holds potential for the depolymerisation of both the biopolymer lignin and epoxy resins applied in wind turbine blades, aircrafts and more. However, this methodology is poorly understood in mechanistic terms. Here, we present a detailed investigation on the triphos-Ru catalysed C–O bond scission on a molecular level. A combination of experimental, spectroscopical and theoretical studies elucidates the reactivity of the ruthenium trimethylenemethane precatalyst, revealing the key roles of ruthenium phenolates in both catalyst activation as well as the catalytic cycle itself. Furthermore, a Ru(0)/Ru(II) oxidative addition into the C–O bond is disclosed, with a triphos-Ru(0) dihydrogen complex as entry point. With the molecular nature of the operating triphos-Ru species and the thermodynamics and kinetics of the catalysis unravelled, improvements of established methods as well as design of related transformations may become possible. Ruthenium complexes with facially coordinating tripodal phosphine ligands are privileged catalysts for a broad range of (de-)hydrogenation-based transformations but the mechanism remains poorly understood. Here the authors present a detailed investigation on the triphos-Ru catalysed C–O bond scission on a molecular level. [ABSTRACT FROM AUTHOR]

In this minireview we survey the challenges and strategies in gold redox catalysis. Gold's reluctance to oxidative addition reactions due to its high redox potential limits its applicability. Initial attempts to overcome this problem focused on the use of sacrificial external oxidants in stoichiometric amounts to bring Au(I) compounds to Au(III) reactive species. Recently, innovative approaches focused on employing hemilabile ligands, which are capable of coordinating to Au(I) and stabilizing square‐planar Au(III) intermediates, thus facilitating oxidative addition steps and enabling oxidant‐free catalysis. Notable examples include the use of the (P^N) bidendate MeDalphos ligand to achieve various cross‐coupling reactions via oxidative addition Au(I)/Au(III). Importantly, hemilabile ligand‐enabled catalysis allows merging oxidative addition with π‐activation, such as oxy‐ and aminoarylation of alkenols and alkenamines using organohalides, expanding gold's versatility in C−C and C‐heteroatom bond formations and unprecedented cyclizations. Moreover, recent advancements in enantioselective catalysis using chiral hemilabile (P^N) ligands are also surveyed. Strikingly, versatile bidentate (C^N) hemilabile ligands as competitors of MeDalphos have appeared recently, by designing scaffolds where phosphine groups are substituted by N‐heterocyclic or mesoionic carbenes. Overall, these approaches highlight the evolving landscape of gold redox catalysis and its tremendous potential in a broad scope of transformations. [ABSTRACT FROM AUTHOR]

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon molecules. Herein, we reported the precise immobilization of metal single atoms (M-SAs; M = Ru, Rh, Ir, Pd, Pt, and Au) into a porphyrinic metal-organic framework (MOF) of PCN-222 (PCN = porous coordination network), and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene hydrosilylation. Under solvent-free conditions, Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room temperature. Experimental and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates, which helped to condense the substrates in the cavities of the porous catalysts. Further density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway. [ABSTRACT FROM AUTHOR]

The rational design of efficient bimetallic nanoparticle (NP) catalysts is challenging due to the lack of theoretical understanding of active components and insights into the mechanisms of a specific reaction. Here, we report the rational design of nanoreactors comprising hollow carbon sphere‐confined PtNi bimetallic NPs (PtNi@HCS) as highly efficient catalysts for hydrogen generation via ammonia borane hydrolysis in water. Using both density functional theory calculations and molecular dynamics simulations, the effects of an active PtNi combination and the critical synergistic role of a hollow carbon shell on the molecule diffusion adsorption behaviors are explored. Kinetic isotope effects and theoretical calculations allow the clarification of the mechanism, with oxidative addition of an O–H bond of water to the catalyst surface being the rate‐determining step. The remarkable catalytic activity of the PtNi@HCS nanoreactor was also utilized for successful tandem catalytic hydrogenation reactions, using in situ‐generated H2 from ammonia borane with high efficiency. The concerted design, theoretical calculations, and experimental work presented here shed light on the rational elaboration of efficient nanocatalysts and contribute to the establishment of a circular carbon economy using green hydrogen. [ABSTRACT FROM AUTHOR]

The possible catalytic mechanism was proposed and studied comprehensively at the M062X/6-31G(d,p) level of theory for a reported chemoselective intermolecular SN2 nucleophilic substitution of aldehydes with alkanolamine. The calculated results show that the catalytic cycle occurs through six stages, namely, the nucleophilic attack of active N-heterocyclic carbene (NHC) on the substrate, generation of the Breslow intermediate, oxidative addition of NBS and alkanolamine, SN2 nucleophilic substitution, Et3N-assisted debromination, and finally regeneration of the NHC along with the release of the product. The results show that TSs of the C–N or C–O bond formation is the key transition state that determines the chemoselectivity of the title reaction. Moreover, our results demonstrated that the N-bromoamine intermediate is more favorable both thermodynamically and kinetically than hypobromite by 14.2 kcal mol−1, which is consistent with the fact that only the N-acylation product was observed in the experiment. In addition, we found that alkanolamine not only acts as a reactant but also as a proton-shuttle and stabilizer to stabilize the structure of the favored chemoselective transition state by multiple N–H⋯N, N–H⋯O and C–H⋯Br− noncovalent interactions. Et3N firstly acts as a base to promote the formation of the active catalyst NHC, then the protonated Et3N acts as a proton-shuttle to accelerate the Breslow intermediate formation and decrease the activation barrier. The Parr functions and frontier molecular orbital analyses of key species indicate that NHC remarkably enhances the nucleophilicity of the substrate aldehyde, leading to a significant increase of the HOMO energy and a moderate increase of the LUMO energy. We hope this work could provide deeper insights into the fundamental mechanisms of the Et3N-assisted NHC-catalyzed SN2 substitution reactions. [ABSTRACT FROM AUTHOR]

Chemoselective monoborylation of methane in high yield is a grand challenge. We have developed a metal–organic framework confined pyridylimine-iridium hydride catalyst, which is efficient in methane C–H borylation using bis(pinacolato)diboron to afford methyl boronic acid pinacol ester in 98% GC-yield at 130 °C with a TON of 196. Mechanistic investigation suggests the oxidative addition of methane to IrIII(Bpin)2(H) species to form IrV(Bpin)2(CH3)(H)2 as the turnover limiting step. [ABSTRACT FROM AUTHOR]

This article discusses a study on the late-stage functionalization of pharmaceutical drugs using ruthenium-catalyzed C-H activation. The researchers focused on introducing N-Aryltriazoles and Tetrazoles into drug molecules, as these structures have the potential to enhance their activity. The method described in the article utilizes accessible dibenzothiophenium salts for the C-H arylation, allowing for the incorporation of these motifs into various bioactive compounds. The study demonstrates that the method is cost-effective, efficient, and compatible with complex dibenzothiophenium salts derived from pharmaceuticals and natural products. Mechanistic studies were conducted to understand the reaction mechanism, and the researchers proposed a catalytic cycle involving the formation of an active catalytic species. Overall, this study provides a mild and versatile method for the synthesis of medicinally relevant compounds. [Extracted from the article]

The reactions of triflamide with camphene in nitriles in the presence of N-bromosuccinimide (NBS) and N-iodosuccinimide (NIS) have been studied. The reactions in isobutyronitrile led to the formation of a number of products, including dibromide, camphenol, bromoamidation product, and the corresponding amidines. Two isomeric benzamidines were obtained in benzonitrile in the presence of NBS. One of these was the skeletal rearrangement product, and the other retained the initial structure. The reaction of camphene with NIS in benzonitrile produced a similar mixture of isomers containing iodine instead of bromine. [ABSTRACT FROM AUTHOR]

The reaction of [Ru2(CO)4(µ-H)(µ-PtBu2)(µ-Ph2PCH2PPh2)] (1) with the diazonium salts [PhN2]BF4 and [p-BrC6H4N2]BF4 in dichloromethane at T = 273 K was investigated. The oxidative addition afforded the products [Ru2(CO)4(µ-H)(µ-PtBu2)(µ-Ph2PCH2PPh2)(µ-N2Ph)]BF4 (2a) and [Ru2(CO)4(µ-H)(µ-PtBu2)(µ-Ph2PCH2PPh2)(µ-N2C6H4-p-Br)]BF4 (2b) in good yields. The products have been characterized by NMR and IR spectroscopy and mass spectrometry and the molecular structure of 2a has been determined by a single-crystal X-ray diffraction analysis (monoclinic, space group P21/m, Z = 2). [ABSTRACT FROM AUTHOR]

Because internal alkenes are more challenging synthetic targets than terminal alkenes, metal‐catalyzed olefin mono‐transposition (i.e. positional isomerization) approaches have emerged to afford valuable E‐ or Z‐ internal alkenes from their complementary terminal alkene feedstocks. However, the applicability of these methods has been hampered by lack of generality, commercial availability of precatalysts, and scalability. Here, we report a nickel‐catalyzed platform for the stereodivergent E/Z‐selective synthesis of internal alkenes at room temperature. Commercial reagents enable this one‐carbon transposition of terminal alkenes to valuable E‐ or Z‐internal alkenes via a Ni−H‐mediated insertion/elimination mechanism. Though the mechanistic regime is the same in both systems, the underlying pathways that lead to each of the active catalysts are distinct, with the Z‐selective catalyst forming from comproportionation of an oxidative addition complex followed by oxidative addition with substrate and the E‐selective catalyst forming from protonation of the metal by the trialkylphosphonium salt additive. In each case, ligand sterics and denticity control stereochemistry and prevent over‐isomerization. [ABSTRACT FROM AUTHOR]

A detailed computational mechanistic study of the copper-catalysed three-component-type electrophilic carboamination of terminal alkynes with benzyne and an archetypal O-benzoylhydroxylamine electrophile is presented. Probing various plausible pathways for relevant elementary steps and scrutinising performance degradation pathways, with the aid of a reliable computational protocol applied to a realistic catalyst model combined with kinetic analysis, identified the pathways preferably traversed in productive catalysis. It entails rapid alkynylcupration of in situ generated benzyne to deliver the arylcopper nucleophile that undergoes amination with the O-benzoylhydroxylamine electrophile to afford copper benzoate. Umpolung-enabled electrophilic amination favours a multistep SN2-type oxidative addition/N–C bond-forming reductive elimination sequence involving a short-lived formal {P^P}CuIII carboxylate amido aryl intermediate. SN2-type displacement of the benzoate leaving group at the arylcopper nucleophile, which represents the catalyst resting state, is predicted to be the turnover limiting step. Alkynolysis transforms copper benzoate back to catalytically competent alkynylcopper. The computational probe of a wider range of substrates reveals that only severely ring-strained C6-arynes, C6-cycloalkynes and electron-deficient cyclopropenes featuring a highly reactive C≡C linkage could replace benzyne. Moreover, strict control of stationary benzyne concentration is indispensable for electrophilic carboamination to ever become achievable. [ABSTRACT FROM AUTHOR]

This article provides an overview of the progress and challenges in the field of nickel-catalyzed C–H activation. It emphasizes the importance of this process in converting readily available chemicals into valuable small molecules. The authors compare nickel and palladium catalysts, discussing their reactivity and mechanistic features. The article also highlights the need for further research to understand the mechanisms involved and to develop more efficient transformations. It explores the use of different bases and directing groups, as well as the thermochemical properties and selectivity of the reactions. The text includes examples of primary C-H activation reactions and discusses recent developments in this area. It also addresses the limitations and future directions for research, such as the preference for methyl groups and the exploration of more remote C-H groups. [Extracted from the article]

Transition‐metal (TM) catalyzed reaction of gem‐difluorinated cyclopropanes (gem‐DFCPs) has drawn much attention recently. The reaction generally occurs via the activation of the distal C─C bond in gem‐DFCPs by a low‐valent TM through oxidative addition, eventually producing mono‐fluoro olefins as the coupling products. However, achieving regioselective activation of the proximal C─C bond in gem‐DFCPs that overcomes the intrinsic reactivity via TM catalysis remains elusive. Here, a new reaction mode of gem‐DFCPs enabled by high‐valent copper catalysis, which allows exclusive activation of the congested proximal C─C bond is presented. The reaction that achieves fluoroarylation of gem‐DFCPs uses NFSI (N‐fluorobenzenesulfonimide) as electrophilic fluoro reagent and arenes as the C─H nucleophiles, enabling the synthesis of diverse CF3‐containing scaffolds. It is proposed that a high‐valent copper species plays an important role in the regioselective activation of the proximal C─C bond possibly via a σ‐bond metathesis. [ABSTRACT FROM AUTHOR]

Previous mass spectrometric (MS) studies demonstrated that singly charged hydration clusters of manganese ions [Mn-(H2O)n]+ were, on one hand, highly reactive toward intracluster water insertion but, on the other hand, inert toward nitrous oxide activation. This contrast in reactivity has been rationalized by our present theoretical investigation for the interconversion between the pristine Mn-(I) monovalent form as a monatomic ion in [MnI(H2O)n]+ and the oxidized Mn-(III) trivalent form as a hydride–hydroxide in [HMnIIIOH-(H2O)n−1], as well as their reactivity toward nitrous oxide activation. Our theoretical interpretations are supported with quantum chemical calculations based on density functional theory (DFT), performed systematically for the cluster-size range of n = 1 – 12. Our DFT results show that water insertion is kinetically and thermodynamically favorable for n ≥ 8, suggesting [HMnIIIOH-(H2O)n−1]+ is the predominant form, as observed in previous MS experiments. While [MnI(H2O)n]+ is capable of N2O reduction, the process of which is highly exothermic, similar reactions are unfavorable with [HMnIIIOH-(H2O)n−1]+, which can only form weakly bound adducts with N2O. This work demonstrates the masking effect of water molecules over the high reactivity of the hydrated Mn-(I) center and sheds light on the potential roles of water in transition metal systems. [ABSTRACT FROM AUTHOR]

An unprecedented electrochemical oxidative trifunctionalization of olefins with diaryl disulfides/aryl thiols and N-chlorosuccinimide in an aqueous system is developed. Two C–Cl bonds, one C–S bond, and one S=O bond are produced simultaneously in one step from simple and commercially available starting materials with clean energy. This tandem methodology features as mild reaction conditions, transition metal and additional oxidant free, broad substrate scope, good functional group compatibility, and gram scale preparation. [ABSTRACT FROM AUTHOR]

The development of new methods for regio‐ and stereoselective activation of C−O bonds in ethers holds significant promise for synthetic chemistry, offering advantages in terms of environmental sustainability and economic efficiency. Moreover, the C−N atropisomers represent a fascinating and crucial chiral system, extensively found in natural products, pharmaceutical leads, and the frameworks of advanced materials. In this work, we have introduced a nickel‐catalyzed regio‐ and enantioselective carbon‐oxygen arylation reaction for atroposelective synthesis of N‐arylisoquinoline‐1,3(2H,4H)‐diones. The high regioselectivity of C−O cleavage benefits from the high stability of the in situ formed (amido)ethenolate via oxidative addition. Additionally, the self‐activation of the aryl C−O bond facilitates the reaction under mild conditions, leading to outstanding enantioselectivities. The diverse post‐functionalizations of the axially chiral isoquinoline‐1,3(2H,4H)‐diones further highlighted the utility of this protocol in preparing valuable C−N atropisomers, including the chiral phosphine ligands. [ABSTRACT FROM AUTHOR]

Polymer–protein bioconjugation offers a powerful strategy to alter the physical properties of proteins, and various synthetic polymer compositions and architectures have been investigated for this purpose. Nevertheless, conjugation of molecular bottlebrush polymers (BPs) to proteins remains an unsolved challenge due to the large size of BPs and a general lack of methods to transform the chain ends of BPs into functional groups suitable for bioconjugation. Here, we present a strategy to address this challenge in the context of BPs prepared by "graft-through" ring-opening metathesis polymerization (ROMP), one of the most powerful methods for BP synthesis. Quenching ROMP of PEGylated norbornene macromonomers with an activated enyne terminator facilitates the transformation of the BP Ru alkylidene chain ends into Pd oxidative addition complexes (OACs) for facile bioconjugation. This strategy is shown to be effective for the synthesis of two BP–protein conjugates (albumin and ERG), setting the stage for a new class of BP–protein conjugates for future therapeutic and imaging applications. [ABSTRACT FROM AUTHOR]

The development of the catalytic regio- and enantioselective hydrofunctionalization of 1,3-dienes remains a challenge and requires deep insight into the reaction mechanisms. We herein thoroughly studied the reaction mechanism of the Ni-catalyzed hydroalkylation of 1,3-dienes with ketones by density functional theory (DFT) calculations. It reveals that the reaction is initiated by stepwise oxidative addition of EtO-H followed by 1,3-diene migratory insertion to generate the alkylnickel(II) intermediate, rather than the experimentally proposed ligand-to-ligand hydrogen transfer (LLHT) mechanism. In addition, we rationalized the role of tBuOK in the subsequent addition of enolate of ketone and transmetalation process. Based on the whole catalysis, the C C reductive elimination step, turns out to be the rate- and enantioselectivity-determining step. Furthermore, we disclosed the origins of the regio- and enantioselectivity of the product, and found that the 1,2-selectivity lies in the combination effects of the ligand-substrate electrostatic interactions, orbital interactions and Pauli repulsions, while the enantioselectivity mainly arises from substrate-ligand steric repulsions. Based on mechanistic study, new biaryl bisphosphine ligands affording higher enantioselectivity were designed, which will help to improve current catalytic systems and develop new transition-metal-catalyzed hydroalkylations. [ABSTRACT FROM AUTHOR]

The oxidative addition of methyl iodide or molecular iodine to the bis(С,N-chelate) deprotonated diaminocarbene platinum(II) complexes [Pt{C(N(H)Ar)(NC(N(H)Ph)N(Ph)}2] (Ar = C6H3-2,6-Me2 (Xyl), C6H2-2,4,6-Me3 (Mes), and C6H4-4-Me (pTol)) affords the corresponding platinum(IV) derivatives in a yield of 89–99%. The addition of CF3CO2H is accompanied by the protonation of the nitrogen atoms of the diaminocarbene fragment to form the cationic complexes [PtI(X)-{C(N(H)Ar)(NC-(N(H)Ph)N(Ph)}2]CF3CO2H (X = Me, I). The structures of the compounds are determined by elemental analysis; high resolution mass spectrometry with electrospray ionization (ESI HRMS); IR spectroscopy; 1H, 13C{1H}, 19F{1H}, and 195Pt{1H} NMR spectroscopy; 2D NMR spectroscopy (1H,1Н COSY, 1H,1Н NOESY, 1H,13C HSQC, 1H,13C HMBC, 1H,15N HSQC, 1H,15N HMBC), and X-ray diffraction (XRD) and thermogravimetric analyses. The synthesized platinum(IV) complexes are thermally stable to 200–260°C and are electroneutral molecules with the octahedral coordination sphere formed by two deprotonated diaminocarbene C,N‑chelate substituents and iodine and methyl or two iodine atoms localized in the apical positions. [ABSTRACT FROM AUTHOR]

The oxidative addition of methyl iodide or molecular iodine to the bis(С,N-chelate) deprotonated diaminocarbene platinum(II) complexes [Pt{C(N(H)Ar)(NC(N(H)Ph)N(Ph)}2] (Ar = C6H3-2,6-Me2 (Xyl), C6H2-2,4,6-Me3 (Mes), and C6H4-4-Me (pTol)) affords the corresponding platinum(IV) derivatives in a yield of 89–99%. The addition of CF3CO2H is accompanied by the protonation of the nitrogen atoms of the diaminocarbene fragment to form the cationic complexes [PtI(X)-{C(N(H)Ar)(NC-(N(H)Ph)N(Ph)}2]CF3CO2H (X = Me, I). The structures of the compounds are determined by elemental analysis; high resolution mass spectrometry with electrospray ionization (ESI HRMS); IR spectroscopy; 1H, 13C{1H}, 19F{1H}, and 195Pt{1H} NMR spectroscopy; 2D NMR spectroscopy (1H,1Н COSY, 1H,1Н NOESY, 1H,13C HSQC, 1H,13C HMBC, 1H,15N HSQC, 1H,15N HMBC), and X-ray diffraction (XRD) and thermogravimetric analyses. The synthesized platinum(IV) complexes are thermally stable to 200–260°C and are electroneutral molecules with the octahedral coordination sphere formed by two deprotonated diaminocarbene C,N‑chelate substituents and iodine and methyl or two iodine atoms localized in the apical positions. [ABSTRACT FROM AUTHOR]