Halogen Substitution Research Articles

Mass-independent Dunham analysis of the [13.8] Ω = 3/2 − X2Π3/2 transition of platinum monochloride, PtCl, observed by intracavity laser spectroscopy: Periodic trends in the M+X− bonding model (M = Ni, Pt; X = F, Cl)

The first electronic transition of platinum chloride, PtCl, observed at high resolution has been recorded in absorption using Intracavity Laser Spectroscopy (ILS). The PtCl molecules were produced in a current-regulated RF discharge formed when 0.30–0.60 A was applied to a Pt-lined Cu hollow cathode in a ∼1 Torr Ar/He sputter gas mixture, with a trace amount of CCl4 as the chloride source. The hollow cathode was located within the resonator cavity of either a tunable DCM dye laser operated over the 14,500–16,500 cm−1 range or a Ti:Sapphire laser operated over the 12,890–12,990 cm−1 and 13,255–13,365 cm1 ranges. Effective absorption path lengths ranging from 0.6 to 2.0 km were utilized with the ILS method. Eight band systems were identified and rotationally analyzed as the (0,2), (0,1), (3,0), (4,0), (5,0), (6,0), (6,1), and (7,1) vibrational bands of the [13.8] Ω = 3/2 − X2Π3/2 transition of PtCl. The vibrational assignment was confirmed through isotopologue shift analysis. The ILS data and millimeter- and submillimeter-wave data reported by Okabayashi et al. (2012) were fit to a mass-independent Dunham-type Hamiltonian using PGOPHER. Pt-isotope dependent deviations in the Dunham model were observed in Y″01(Be″), Y′01(Be′), and Y′00(Te′) and treated using field-shift parameters, and these parameters are compared to the reported field-shift effects for other 5d transition metal diatomics. The excited state molecular constants determined in this study are consistent with those of the (4) 3/2 state in the computational study by Zou and Suo (2016). The electronic transitions of NiF, NiCl, and PtF analogous to the [13.8] Ω = 3/2 – X2Π3/2 transition of PtCl have been studied both theoretically and experimentally. The vibrational force constants and relative bond lengths for the MX (M = Ni, Pt; X = F, Cl) molecules suggest that Ni and Pt form similar MX bonds, with NiX bonds being slightly stronger, but a large effect is observed for halogen substitution, with MF force constants being more than twice as large as the corresponding MCl values.

Melt-memory of polyethylenes with halogen substitution: Random vs. precise placement

Polyethylenes with Br, Cl, or F atoms placed at an equal distance of 21 or 15 backbone carbons are known to crystallize as homopolymers, accommodating the halogen in layered crystallites. In contrast, analogs with a random distribution display a crystallization path dominated by sequence-length selection. A consequence of the sequence selection of random copolymers is a constrained interlamellar region and broader melting peaks displaced at higher temperatures than analog systems with the precise placement. Precision and random ethylene-vinyl halides are excellent models to substantiate as a general behavior the strong melt-memory observed in random ethylene 1-alkene copolymers, which contrasts with a much weaker or lack of melt-memory seen in linear polyethylene. While precision polyethylenes with Br, Cl, or F placed on each 21st or 15th backbone carbon show negligible deviation in crystallization rate above the observed melting, the increase in crystallization rate of analogs with the random distribution is observed even from melts 60° above the observed melting point. These data give further evidence of the sharp difference of melt-memory behavior between homopolymers and random copolymers, regardless of whether the co-unit participates in the crystalline regions. Differences in melt-annealing behavior, and a recrystallization of precision polyethylenes that depends on the polymorph that melts prior a subsequent cooling, are also highlighted.

Systematic study of the substitution effect on the tetrel bond between 1,4-diazabicyclo[2.2.2]octane and TH3X.

A tetrel bond was characterized in the complexes of 1,4-diazabicyclo[2.2.2]octane (DABCO) with TH3X (T = C, Si, Ge; X= –Me, –H, –OH, –NH2, –F, –Cl, –Br, –I, –CN, –NO2). DABCO engages in a weak tetrel bond with CH3X but a stronger one with SiH3X and GeH3X. SiH3X is favorable to bind with DABCO relative to GeH3X, inconsistent with the magnitude of the σ-hole on the tetrel atom. The methyl group in the tetrel donor weakens the tetrel bond but an enhancing effect is found for the other substituents, particularly –NO2. The substitution effect is also related to the nature of the tetrel atom. The halogen substitution from F to I has a weakening effect in the CH3X complex but an enhancing effect in the SiH3X complex and a negligible effect in the GeH3X complex. The above abnormal results found in these complexes can be partly attributed to the charge transfer from the lone pair on the nitrogen atom of DABCO into the anti-bonding orbital σ*(T–X) of TH3X. The stability of both SiH3X and GeH3X complexes is primarily controlled by electrostatic interactions and polarization.

Combined experimental and theoretical investigations of Ba3GaS4I: interesting structural transformation originated from halogen substitution.

Inorganic chalcohalides have emerged as promising functional materials for a range of applications. However, most of them are chlorides and bromides, while iodides are still rare. Herein, a new quaternary iodine-based chalcohalide Ba3GaS4I has been acquired by the reaction of BaS, Ga, S and BaI2 at 1173 K. Single-crystal XRD analysis reveals that Ba3GaS4I has a centrosymmetric structure (orthorhombic, space group Cmcm, a = 6.991(3) Å, b = 15.910(7) Å, c = 9.698(4) Å, V = 1078.6(7) Å3, and Z = 4) and consists of isolated [GaS4] tetrahedra with charge-balanced Ba2+ cations and I- anions. Ba3GaS4I can be regarded as the product of chemical substitution of Ba3GaS4X (X = Cl, Br), which adopts a different space group, Pnma. The influences of the halogen elements on the bandgap and birefringence have been discussed through first principles calculations and structural comparison.

Theoretical study of synergetic effect between halogenation and pyrazine substitutions on transport properties of silylethynylated pentacene

Combining quantum-tunneling-effect-enabled hopping theory with kinetic Monte Carlo simulation and dynamic disorder effects, the charge transport properties of a series of N-hetero 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-PEN) derivatives with halogen substitutions were studied.

Influence of halogen substitution on aggregation-induced near infrared emission of borondifluoride complexes of 2′-hydroxychalcones

In this study, we investigate the role of halogen atoms on the fluorescence emission properties of borondifluoride complexes of 2′-hydroxychalcones in the solid-state.

Exploring the effects of axial halogen substitutions of boron subphthalocyanines on the performance of BsubPC/C60 organic solar cells: a DFT/TDDFT-based computational study

A systematic study on the effects of axial halogen substitutions of Cl atom on the optical and physical properties of subphthalocyanine/C60 solar cells by combining a DFT/TDDFT study and available experimental data.

Versatile coordination and C-H activation of a multi-donor phosphinoferrocene carboxamide ligand in Pd(ii) complexes.

A multi-donor phosphinoferrocene carboxamide, FcCONHCH2CH2PPh2 (1, Fc = ferrocenyl), was prepared, converted into the corresponding phosphine oxide 1O and phosphine selenide 1Se and, mainly, studied as a ligand in Pd(ii) complexes. In its native form, amide 1 preferentially coordinated soft Pd(ii) as a simple phosphine, giving rise to mixtures of cis and trans-[PdX2(1-κP)2] (2; X = Cl (a), Br (b), and I (c)), wherein the isomer ratios depended on the auxiliary halide ligand or, alternatively, to the complex [(LNC)PdCl(1-κP)] (6, LNC = 2-[(dimethylamino)methyl-κN]phenyl-κC1). This coordination mode was nevertheless easily changed when creating a vacant coordination site at the palladium. Thus, treatment of 2a with NH4[PF6] in the presence of free 1 produced [PdCl(1-κP)3][PF6] (3), while complete halogen removal with a Ag(i) salt led to cationic complexes cis-[Pd(1-κ2O,P)2]X2 (4, X = CF3SO3 (a), ClO4 (b), BF4 (c)) or [(LNC)Pd(1-κ2O,P)]X (7a and 7b), containing seven-membered O,P-chelate rings. In contrast, amide nitrogen deprotonation with KOt-Bu followed by spontaneous intramolecular halogen substitution resulted in the transformation of 6 into the chelate complex [(LNC)Pd{(1- H)-κ2N,P}] (8) featuring a five-membered N,P-chelate ring, and in the conversion of 2a and 2b into the product of C-H bond activation [Pd{Fe(η5-C5H3CONCH2CH2PPh2-κ3C,N,P)(η5-C5H5)}(1-κP)] (5), with doubly chelating deprotonated 1. Importantly, complexes 2-4-5 and 6-7-8 were mutually interconverted in triads (by protonation/deprotonation and by halide addition/abstraction), which highlights the flexible coordination and chemical stability of ligand 1. The crystal structures of 1O·½H2O, trans-2a·MeCN, trans-2b·3C2H4Cl2, trans-2c·2.5C2H4Cl2, 4a·CH2Cl2, 5·3CHCl3·Et2O, and 8 were determined by single-crystal X-ray diffraction analysis, and the representative compounds were studied by cyclic voltammetry.

Dissecting the Conformational and Interaction Topological Landscape of N-ethynylphenylbenzamide by the Device of Polymorphic Diversity

The modern day crystal engineering approach aims at the exploration of the structural landscape of a molecule to perceive the phenomenon of the crystallization event for that molecule. The present study focuses on thorough experimental and computational investigations of the crystal landscape in the conformationally flexible N-ethynylphenylbenzamide molecule. We have performed the chemical modification of the parent unsubstituted N-ethynylphenylbenzamide molecule on the benzoyl ring by different halogen substitutions (monofluoro/difluoro/trifluoromethyl/chloro/bromo) at ortho/meta/para positions and employed the device of the polymorphophore concept to access a large number of experimentally viable structures in the landscape. In a total of 11 substituents as variants in molecules, the parent molecule displays monomorphic behavior, and in the remaining 10 molecules, each exists in several polymorphic forms resulting in a total of 28 single-component crystal structures. Through the systematic analysis of their conformational preferences in the conformational landscape and classification of the prevalent supramolecular recognition patterns, the interaction topologies of all substituent modified polymorphic structures have been mapped by the quantification of interaction energies of supramolecular synthons followed by a crystal structure prediction study. The combination of all studies demonstrates the robustness of primary synthon topology (formed by N–H···O═C/ π···π stacking interaction) and local variation of structures by different secondary interaction preferences (weak C–H···O, C–H···π, C–H···F/Cl/Br, and π···π interactions) to construct a nearly similar global interaction topology of molecules in all crystal structures and represents a general interaction topological landscape.

Halogen Substitution Influences Ketamine Metabolism by Cytochrome P450 2B6: In Vitro and Computational Approaches.

Ketamine is analgesic at anesthetic and subanesthetic doses, and it has been used recently to treat depression. Biotransformation mediates ketamine effects, influencing both systemic elimination and bioactivation. CYP2B6 is the major catalyst of hepatic ketamine N-demethylation and metabolism at clinically relevant concentrations. Numerous CYP2B6 substrates contain halogens. CYP2B6 readily forms halogen-protein (particularly Cl-π) bonds, which influence substrate selectivity and active site orientation. Ketamine is chlorinated, but little is known about the metabolism of halogenated analogs. This investigation evaluated halogen substitution effects on CYP2B6-catalyzed ketamine analogs N-demethylation in vitro and modeled interactions with CYP2B6 using various computational approaches. Ortho phenyl ring halogen substituent changes caused substantial (18-fold) differences in Km, on the order of Br (bromoketamine, 10 μM) < Cl < F < H (deschloroketamine, 184 μM). In contrast, Vmax varied minimally (83-103 pmol/min/pmol CYP). Thus, apparent substrate binding affinity was the major consequence of halogen substitution and the major determinant of N-demethylation. Docking poses of ketamine and analogs were similar, sharing a π-stack with F297. Libdock scores were deschloroketamine < bromoketamine < ketamine < fluoroketamine. A Bayesian log Km model generated with Assay Central had a ROC of 0.86. The probability of activity at 15 μM for ketamine and analogs was predicted with this model. Deschloroketamine scores corresponded to the experimental Km, but the model was unable to predict activity with fluoroketamine. The binding pocket of CYP2B6 also suggested a hydrophobic component to substrate docking, on the basis of a strong linear correlation ( R2 = 0.92) between lipophilicity ( Alog P) and metabolism (log Km) of ketamine and analogs. This property may be the simplest design criteria to use when considering similar compounds and CYP2B6 affinity.

Spin waves near the edge of halogen substitution induced magnetic order in Ni(Cl1−xBrx)2·4SC(NH2)2

We report an inelastic neutron scattering study of magnetic excitations in a quantum paramagnet driven into a magnetically ordered state by chemical substitution, namely Ni(Cl$_{1-x}$Br$_x$)$_2$$\cdot$4SC(NH$_2$)$_2$ with $x=0.21(2)$. The measured spectrum is well accounted for by the generalized spin wave theory (GSWT) approach [M. Matsumoto and M. Koga, [J. Phys. Soc. Jap. 76, 073709 (2007)]. This analysis allows us to determine the effective Hamiltonian parameters for a direct comparison with those in the previously studied parent compound and `underdoped' system. The issue of magnon lifetimes due to structural disorder is also addressed.

Inducing Favorable Cation Antisite by Doping Halogen in Ni-Rich Layered Cathode with Ultrahigh Stability.

The cation antisite is the most recognizable intrinsic defect type in nickel‐rich layered and olivine‐type cathode materials for lithium‐ion batteries, and important for electrochemical/thermal performance. While how to generate the favorable antisite has not been put forward, herein, by combining first‐principles calculation with neutron powder diffraction (NPD) study, a defect inducing the favorable antisite mechanism is proposed to improve cathode stability, that is, halogen substitution facilitates the neighboring Li and Ni atoms to exchange their sites, forming a more stable local octahedron of halide (LOSH). According to the mechanism, it is demonstrated by NPD that F‐doping not only induces the antisite formation in layered LiNi0.85Co0.075Mn0.075O2 (LNCM), but also increases the antisite concentration linearly. F substitution (1%) induces 5.7% antisite, and it displays an excellent capacity retention of 94% at 1 C for 200 cycles under 25 °C, outstanding high temperature cyclability (153.4 mAh·g–1 at 1 C for 120 cycles under 55 °C). The onset decomposition temperature increases by 48 °C. The ultrahigh cycling/thermal stability is attributed to the stronger LOSH, and it keeps the structural integrity after long cycling and develops an electrostatic repulsion force between oxygen layers to increase the lattice parameter c, which benefits Li‐ion migration.

Tuning the Photophysical Properties of Symmetric Squarylium Dyes: Investigation on the Halogen Modulation Effects.

A series of symmetric squarylium dyes (SQDPA-X) with different halogen (X=F, Cl, Br, I) substituents have been developed. The photophysical properties could be facilely tuned by the halogen modulation effects. The strategy of incorporating different halogen substitutions into AIE active luminogens enables a facile approach for exploring new intriguing organic fluorescent dyes.

Enhanced High Voltage Performance of Chlorine/Bromine Co-Doped Lithium Nickel Manganese Cobalt Oxide

The chlorine (Cl) and bromine (Br) co-doped lithium nickel manganese cobalt oxide (LiNi1/3Co1/3Mn1/3O2) was successfully synthesized by the molten salt method. The synthesized LiNi1/3Co1/3Mn1/3O2 compound demonstrates spherical morphology, which is formed by aggregated spherical-like or polygon primary particles. Halogen substitution would contribute to the growth of the primary particles. The LiNi1/3Co1/3Mn1/3O2 compound has the typical hexagonal layered structure, and no impurity phase is detected. The surface oxidation state of the compound is improved after Cl and Br substitution. Moreover, the Cl and Br co-doped LiNi1/3Co1/3Mn1/3O2 compound exhibits both improved rate capacity and cycle stability at a high voltage (4.6 V) compared with the pristine LiNi1/3Co1/3Mn1/3O2. The initial discharge capacities of Cl and Br co-doped LiNi1/3Co1/3Mn1/3O2 are 208.9 mAh g−1, 200.6 mAh g−1, 188.2 mAh g−1, 173.3 mAh g−1, and 157.1 mAh g−1 at the corresponding rates of 0.1C, 0.2C, 0.5C, 1C, and 3C respectively. The capacity retention at 1C after 50 cycles is increased from 81.1% to 93.2% by co-doping. The better contact between the electroactive particles of the electrode and the smaller resistance enhance the electric conductivity of the Cl and Br co-doped LiNi1/3Co1/3Mn1/3O2 cathode. The synthesized LiNi1/3Co1/3Mn1/3O2 is a promising cathode material for a high-power and large-capacity lithium-ion battery.

C-Halogenated 9,10-Diboraanthracenes: How the Halogen Load and Distribution Influences Key Optoelectronic Properties.

9,10-Dihydro-9,10-diboraanthracenes (DBAs) have low-energy LUMOs and narrow HOMO-LUMO gaps and are thus attractive electron-transporting and light-emitting materials in optoelectronic devices. A systematic series of ten C-halogenated 9,10-(Mes)2 -DBAs was synthesized and studied by cyclic voltammetry, UV/Vis absorption and emission spectroscopy, and quantum-chemical calculations (Mes=mesityl). We probed the influence of the nature of the halogen atoms and the halogen substitution patterns on key optoelectronic properties of the DBAs. All 9,10-(Mes)2 derivatives can be reversibly reduced at the DBA cores and at electrode potentials between E1/2 Red1 =-1.84 and -1.26 V (vs. FcH/FcH+ ). The most bathochromic UV/Vis absorption and the fluorescence emission of each DBA correspond to an ICT transition between the Mes rings and the DBA core. Br substituents lower the DBA LUMO energy and narrow the energy gap to the highest degree along the series F<Cl<Br. Halogen atoms located at 1,4,5,8-positions are more influential than those at 2,3,6,7-positions. An increasing fluorine load continuously decreases the LUMO levels and HOMO-LUMO gaps. Colorless octafluoro- and tetrafluoro-DBAs form colored and fluorescent π-stacked hetero dimers with anthracene in C6 H6 solutions and in the solid state. The sterically congested 1,5-(ThMe)2 -9,10-(Mes)2 -DBA was prepared in 74 % yield from 1,5-(Br)2 -9,10-(Mes)2 -DBA and Me3 Sn-ThMe through a Stille-type C-C coupling reaction (ThMe=5-Me-2-thienyl).

Influence of π -conjugated cations and halogen substitution on the optoelectronic and excitonic properties of layered hybrid perovskites

Low-cost chemical engineering of two-dimensional layered hybrid halide perovskite structures allows for the design of hybrid semiconductor quantum wells with tailored room-temperature excitonic optical absorption, emission, and charge carrier transport properties. Here density functional theory and the Bethe-Salpeter equation are used to predict the electronic structure and optical response of layered perovskites with two representative single-ring conjugated organic spacers, ammonium-propyl-imidazole (API) and 2-phenethylammonium (PEA). The inorganic perovskite quantum well properties are further tuned by analyzing the effect of halogen (X = I, Br, Cl) substitution. We found that visible light absorption occurs primarily within the perovskite layer and that UV light absorption induces partial electron-hole separation between layers. In addition, a strong exciton binding energy and influence on absorption spectrum is found by solving the Bethe-Salpeter equation. Our results suggest that further engineering is necessary beyond the single-ring limit, by introducing more conjugated rings and/or heavier nuclei into the organic spacer. This is a promising future direction to achieve photoinduced charge separation and more generally hybrid heterostructures with attractive optoelectronic properties.

Structures and energetic properties of 4-halobenzamides.

The amide bond represents one of the most fundamental functional groups in chemistry. The properties of amides are defined by amidic resonance (nN→π*C=O conjugation), which enforces planarity of the six atoms comprising the amide bond. Despite the importance of 4-halo-substituted benzamides in organic synthesis, molecular interactions and medicinal chemistry, the effect of 4-halo-substitution on the properties of the amide bond in N,N-disubstituted benzamides has not been studied. Herein, we report the crystal structures and energetic properties of a full series of 4-halobenzamides. The structures of four 4-halobenzamides (halo = iodo, bromo, chloro and fluoro) in the N-morpholinyl series have been determined, namely 4-[(4-halophenyl)carbonyl]morpholine, C11H12XNO2, for halo = iodo (X = I), bromo (X = Br), chloro (X = Cl) and fluoro (X = F). Computations have been used to determine the effect of halogen substitution on the structures and resonance energies. 4-Iodo-N-morpholinylbenzamide crystallized with a significant distortion of the amide bond (τ + χN = 33°). The present study supports the correlation between the Ar-C(O) axis twist angle and the twist angle of the amide N-C(O) bond. Comparison of resonance energies in synthetically valuable N-morpholinyl and N-piperidinyl amides demonstrates that the O atom of the morpholinyl ring has a negligible effect on amidic resonance in the series.

Govindasamy Mugesh

Angewandte Chemie International EditionVolume 58, Issue 3 p. 662-662 Author ProfileFree Access Govindasamy Mugesh First published: 30 August 2018 https://doi.org/10.1002/anie.201809460Citations: 2AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Graphical Abstract “When I was eighteen I wanted to be a farmer. The natural talent I would like to be gifted with is the ability to learn new languages quickly …” Find out more about Govindasamy Mugesh in his Author Profile. Govindasamy Mugesh The author presented on this page has recently published his 10th article since 2010 in Angewandte Chemie: “Remarkable Effect of Halogen Substitution on the Membrane Transport of Fluorescent Molecules in Living Cells”: H. Ungati, V. Govindaraj, G. Mugesh, Angew. Chem. Int. Ed. 2018, 57, 8989; Angew. Chem. 2018, 130, 9127. The work of G. Mugesh has been featured on the cover of Angewandte Chemie: “Chemistry and Biology in the Biosynthesis and Action of Thyroid Hormones”: S. Mondal, K. Raja, U. Schweizer, G. Mugesh, Angew. Chem. Int. Ed. 2016, 55, 7606; Angew. Chem. 2016, 128, 7734. Date of birth: May 29, 1970 Position: Professor, Indian Institute of Science, Bangalore E-mail: mugesh@iisc.ac.in Homepage: http://ipc.iisc.ac.in/gm.php ORCID: 0000-0002-5389-5309 Education: 1993 MSc, Bharathidasan University, Tiruchirappalli 1998 PhD with Prof. Harkesh B. Singh, Indian Institute of Technology, Bombay 2000–2001 Postdoctoral fellow with Prof. W.-W. du Mont, Technische Universität Braunschweig 2001–2002 Postdoctoral fellow with Prof. K. C. Nicolaou, The Scripps Research Institute, La Jolla Awards: 2011 CRSI Bronze Medal; 2011 AstraZeneca Excellence in Chemistry Award; 2012 Shanti Swarup Bhatnagar Prize; 2015 JC Bose Fellowship, Science and Engineering Research Board; 2017 National Prize for Research on Interfaces of Chemistry and Biology; Current research interests: Artificial enzymes; cellular redox regulation; ferroptosis; fluorescent probes; nitric oxide signaling; thyroid hormones Hobbies: Watching movies, cooking, driving When I was eighteen I wanted to be a farmer. The natural talent I would like to be gifted with is the ability to learn new languages quickly. The biggest challenge facing scientists is too many irrelevant and misleading research problems. My motto is work hard with dedication, serve people, and do not expect anything in return. Looking back over my career, I am satisfied! My favorite saying is “great minds discuss ideas; average minds discuss events; weak minds discuss people”. My favorite time of day is 10.30 am when I take a break and go with my colleagues to the Faculty Club on our beautiful campus for a cup of tea. I advise my students to be honest and help others. My favorite molecule is thyroxine, a simple molecule with amazing functions in the human body. My favorite composer is Isai Gnani Ilaiyaraaja, one of the greatest Indian composers, who wrote music for our every emotion in life. My favorite book is Thirukkural—a 2000-year-old classic Tamil work on ethics, which consists of 1 330 couplets (Kurals), dealing with all aspects of Aram (virtue), Poruḷ (wealth), and Inbam (love). My 5 top papers: 1“An antioxidant nanozyme that uncovers the cytoprotective potential of vanadia nanowires”: A. A. Vernekar, D. Sinha, S. Srivastava, P. U. Paramasivam, P. D'Silva, G. Mugesh, Nature Commun. 2014, 5, 5301. (Turning potentially cytotoxic vanadium into a cytoprotective redox modulator in human cells.) 2“A Chemical Model for the Inner-Ring Deiodination of Thyroxine by Iodothyronine Deiodinase”: D. Manna, G. Mugesh, Angew. Chem. Int. Ed. 2010, 49, 9246– 9249; Angew. Chem. 2010, 122, 9432. (Highlights the importance of two biological trace elements, selenium and iodine, in thyroid hormone activation and metabolism.) 3“Antibiotic Resistance: Mono- and Dinuclear Zinc Complexes as Metallo-β-Lactamase Mimics”: A. Tamilselvi, M. Nethaji, G. Mugesh, Chem. Eur. J. 2006, 12, 7797. (The key role played by metal ions in bacterial drug resistance and inactivation of β-lactam antibiotics.) 4“Biomimetic Studies on Anti-Thyroid Drugs and Thyroid Hormone Synthesis”: G. Roy, M. Nethaji, G. Mugesh, J. Am. Chem. Soc. 2004, 126, 2712. (My first paper as an independent researcher. Selenomethimazole can exert its anti-thyroid action by a mechanism different from that of the sulfur analogue.) 5“Synthesis and Structural Characterization of Monomeric Selenolato Complexes of Zinc, Cadmium, and Mercury”: G. Mugesh, H. B. Singh, R. P. Patel, R. J. Butcher, Inorg. Chem. 1998, 37, 2663. (My first ever publication. An intramolecular coordination strategy to prevent the polymerization that is generally observed for Group 12 metal chalcogenolate complexes.) Citing Literature Volume58, Issue3January 14, 2019Pages 662-662 ReferencesRelatedInformation

Immunostimulatory effect of Zinc Phthalocyanine derivatives on macrophages based on the pro-inflammatory TNFα and IL1β cytokine production levels

In this study, we examined the effect of halogen substitution on the ability of ZnPcs to stimulate or regulate the immune system cells. There have been studies focusing on the usage of Pcs as treatment option against different cancer types. More attention should be paid on their possible positive or negative effects on the immune system for better prognosis rates. We designed and synthesized unique ZnPcs with iodine substitution and further tested their effect on mammalian macrophage cell line. Macrophages are crucial cell types that can define the immune response by cytokine production as well as by antigen presentation to the other immune system cells after phagocytosis of the danger associated molecules. Our results suggest an immunostimulatory role for the iodine substituted ZnPc on macrophages based on the changes in pro-inflammatory cytokine production levels (TNFα, IL1β and IL6). This effect dependent on the presence of iodine; since non-substituted ZnPc did not exert such a stimulatory activity on the macrophages. These results support a possible use of the reagents against the tumor types that would get affected detrimentally by the pro-inflammatory environment.

Haloferrocenes: Syntheses and Selected Reactions

Although haloferrocenes constitute important starting materials for many ferrocene-derived products with importance in a variety of fields such as materials science, medicinal chemistry and catalysis, only relatively few haloferrocenes out of the large number of possible examples have been prepared so far. The first part of this review summarizes the syntheses of all the homo- and heterohaloferrocenes known up to date. The second part summarizes typical reactions of haloferrocenes, namely lithiation followed by trapping with an electrophile, copper-mediated halogen substitution, coupling with formation of diferrocenyl derivatives, ortho-lithiation followed by trapping with an electrophile, palladium-catalyzed coupling reactions and finally miscellaneous reactions.1 Introduction2 Homohaloferrocenes2.1 Fluoroferrocenes2.2 Chloroferrocenes2.3 Bromoferrocenes2.4 Iodoferrocenes3 Heterohaloferrocenes4 Selected Reactions of Haloferrocenes4.1 Lithiation Followed by Trapping with an Electrophile4.2 Copper-Mediated Halogen Substitution4.3 Coupling with Formation of Diferrocenyl Derivatives4.4 ortho-Lithiation of Haloferrocenes4.5 Palladium-Catalyzed Reactions of Haloferrocenes4.6 Miscellaneous Reactions of Haloferrocenes5 Conclusions