Selenium Tetrachloride Research Articles

Bonding properties and crystal packing in β-(SeCl4)4 derived from Hirshfeld Atom Refinement.

Binary chalcogen halogen EX4 species represent intriguing systems in terms of chemical bonding theories, such as hypervalency and stereoactivity of lone electron pairs. Instead of a simple molecular EX4 structure, selenium tetrachloride forms an ionic pair, Cl3Se+Cl-, that assembles into a tetrameric (SeCl4)4 structure, namely, tetra-μ3-chlorido-dodecachloridotetraselenium. This article describes the charge-density analysis of the tetrameric molecule of β-SeCl4 based on the aspherical model obtained from Hirshfeld Atom Refinement of the tetrameric molecule and of an explicit cluster of 15 tetramers that simulates the crystal packing. Deformation density, electron localization function (ELF) and Quantum Theory of Atoms in Molecules (QTAIM) were used to evaluate the bonding situation, the electron-density distribution around the Se atom and the interaction energy of the tetramer.

RETRACTED: Al-Salmi, F.A.; Hamza, R.Z. Efficacy of Vanadyl Sulfate and Selenium Tetrachloride as Anti-Diabetic Agents against Hyperglycemia and Oxidative Stress Induced by Diabetes Mellitus in Male Rats. Curr. Issues Mol. Biol. 2022, 44, 94-104.

Current Issues in Molecular Biology Editorial Office retracts the article titled "Efficacy of Vanadyl Sulfate and Selenium Tetrachloride as Anti-Diabetic Agents against Hyperglycemia and Oxidative Stress Induced by Diabetes Mellitus in Male Rats" [...].

Efficacy of Vanadyl Sulfate and Selenium Tetrachloride as Anti-Diabetic Agents against Hyperglycemia and Oxidative Stress Induced by Diabetes Mellitus in Male Rats.

The use of metals in medicine has grown in popularity in clinical and commercial settings. In this study, the immune-protecting effects and the hypoglycemic and antioxidant activity of vanadyl sulfate (VOSO4) and/or selenium tetrachloride (Se) on oxidative injury, DNA damage, insulin resistance, and hyperglycemia were assessed. Fifty male albino rats were divided into five groups, and all treatments were administrated at 9:00 a.m. daily for 60 successive days: control, STZ (Streptozotocin; 50 mg/kg of STZ was given to 6 h fasted animals in a single dose, followed by confirmation of diabetic state occurrence after 72 h by blood glucose estimation at >280 mg/dl), STZ (Diabetic) plus administration of VOSO4 (15 mg/kg) for 60 days, STZ (Diabetic) plus administration of selenium tetrachloride (0.87 mg/Kg), and STZ plus VOSO4 and, after 1/2 h, administration of selenium tetrachloride at the above doses. The test subjects’ blood glucose, insulin hormone, HbA1C, C-peptide, antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, myeloperoxidase, and xanthine oxidase), markers of lipid peroxidation (MDA), and histological sections of pancreatic tissues were evaluated, and a comet assay was performed. Histological sections in pancreas tissues were treated as indicators of both VOSO4 and selenium tetrachloride efficacy, either alone or combined, for the alleviation of STZ toxicity. The genotoxicity of diabetes mellitus was assessed, and the possible therapeutic roles of VOSO4 or selenium tetrachloride, or both, on antioxidant enzymes were studied. The findings show that the administration of VOSO4 with selenium tetrachloride reduced oxidative stress to normal levels, lowered blood glucose levels, and elevated insulin hormone. Additionally, VOSO4 with selenium tetrachloride had a synergistic effect and significantly decreased pancreatic genotoxicity. The data clearly show that both VOSO4 and selenium tetrachloride inhibit pancreatic and DNA injury and improve the oxidative state in male rats, suggesting that the use of VOSO4 with selenium tetrachloride is a promising synergistic potential ameliorative agent in the diabetic animal model.

CHALCOGENATION OF N-ALKENYL DERIVATIVES OF 2-THIOXO-2,3-DIHYDRO QUINAZOLINE-4(1H)-ONE

Oxo- and thio-substituted quinazolines are promising biologically active objects. A special place in a number of quinazolines is occupied by its condensed analogues, namely thiazoloquinazolines, which exhibit antioxidant, antimicrobial and antitumor activity. An effective method for the synthesis of condensed quinazoline derivatives is electrophilic intramolecular cyclization of its unsaturated derivatives. The usage of pharmacoformic chalcogen-containing electrophiles in these reactions has been insufficiently studied. Organochalcogen-containing heterocyclic compounds are the promising biologically active substances with different pharmacological action. Therefore, the study of reactions of electrophilic intramolecular cyclization of N(3)-alkenyl derivatives of 2-thioxo-2,3-dihydroquinazolin-4(1H)-one under the action of chalcogen tetrahalides is an urgent task.
 N (3)-alkenyl derivatives of 2,3-dihydroquinazolin-4(1H)-one were used as the object of study. It was found that the interaction of tellurium tetrabromide with N(3)-alkenyl-2-thioxoquinazolin-4-ones in glacial acetic acid leads to linear hydrobromides of 2-[(tribromotelluro) methyl]-2,3-dihydro-5H-[1,3]thiazolo[2,3-b]quinazolin-5-one.
 In the reaction with N(3)-methallyl-2-thioxo-2,3-dihydroquinazolin-4(1H)-one, individual tellurium tetrachloride was used, which was obtained by passing chlorine over the tellurium. It is proved that halotellurium-induced cyclization of N-methallyl quinazolone with tellurium tetrachloride occurs regioselectively with the formation of 2-methyl-2-[(trichlorotelluro)methyl]-2,3-dihydro-5H- [1,3]thiazolo[2,3-b]quinazoline-5-one hydrochloride of linear structure.
 In order to study the influence of the nature of chalcogen in the electrophilic reagent on the regiochemistry of cyclization in the reaction with N(3)-methallyl-2-thioxo-2,3-dihydroquinazolin-4(1H)-one, obtained in situ selenium tetrachloride was used. The selenochlorination reaction of N(3)-methallyl-2-thioxo-2,3-dihydroquinazolin-4(1H)-one in chloroform gave a linear hydrochloride of 2-methyl-2-[(trichloroseleno)methyl]-2,3-dihydro-5H-[1,3]thiazolo[2,3-b]quinazolin-5-one.
 Thus, the regiochemistry of electrophilic intramolecular cyclization of N(3)-alkenyl-2-thioxo-2,3-dihydroquinazolin-4(1H)-ones by chalcogentetrahalides was investigated and it was proved that the annulationof the thiazoline cycle occurs with the formation of bioperspective bundles of tricyclic heterocycles of linear constitution independently from nature and origin of electrophilic reagent.

Biomimetic Iodofunctionalization of Aromatic and Heteroaromatic Compounds Catalyzed by Selenium Tetrachloride

A biomimetic iodofunctionalization of aromatic and heteroaromatic compounds has been developed using NaI as a source of iodine and 30% H2O2 as a mild oxidant, as well as SeCl4 as a commercially available catalyst in water without a co-solvent. The method affords iodinated compounds in isolated yields of 37 to 99%. The catalytic system has potential for the bromination of aromatic substrates.

The Leptomeninges Produce Prostaglandin D2 Involved in Sleep Regulation in Mice.

Injection of nanomolar amounts of prostaglandin D2 (PGD2) into the rat brain has dose and time-dependent somnogenic effects, and the PGD2-induced sleep is indistinguishable from physiologic sleep. Sleep-inducing PGD2 is produced in the brain by lipocalin-type PGD2 synthase (LPGDS). Three potential intracranial sources of LPGDS have been identified: oligodendrocytes, choroid plexus, and leptomeninges. We aimed at the identification of the site of synthesis of somnogenic PGD2 and therefore, generated a transgenic mouse line with the LPGDS gene amenable to conditional deletion using Cre recombinase (flox-LPGDS mouse). To identify the cell type responsible for producing somnogenic PGD2, we engineered animals lacking LPGDS expression specifically in oligodendrocytes (OD-LPGDS KO), choroid plexus (CP-LPGDS KO), or leptomeninges (LM-LPGDS KO). We measured prostaglandins and LPGDS concentrations together with PGD synthase activity in the brain of these mice. While the LPGDS amount and PGD synthase activity were drastically reduced in the OD- and LM-LPGDS KO mice, they were unchanged in the CP-LPGDS KO mice compared with control animals. We then recorded electroencephalograms, electromyograms, and locomotor activity to measure sleep in 10-week-old mice with specific knockdown of LPGDS in each of the three targets. Using selenium tetrachloride, a specific PGDS inhibitor, we demonstrated that sleep is inhibited in OD-LPGDS and CP-LPGDS KO mice, but not in the LM-LPGDS KO mice. We concluded that somnogenic PGD2 is produced primarily by the leptomeninges, and not by oligodendrocytes or choroid plexus.

The synthesis and characterisation of highly stable and reproducible selenium nanoparticles

ABSTRACTThis paper describes a simple and reproducible solution phase synthesis approach for selenium nanoparticles by reducing selenium tetrachloride in the presence of ascorbic acid. An optimization study with poly (sodium 4-styrenesulfonate) produced stable and spherical narrowly size distributed nanoparticles (46 nm) which are considered highly monodisperse. The presence of selenium nanoparticles was confirmed by UV-visible spectroscopy for surface plasmon resonance (262 nm), elemental dispersive spectroscopy (11 KeV and 12.5 KeV) and size ranges characterized by dynamic light scattering (PDI = 0.04, size range of optimized nanoparticles = 35 nm to 75 nm), and visualized using scanning and transmission electron microscopy.

Decreased Prostaglandin D2 Levels in Major Depressive Disorder Are Associated with Depression-Like Behaviors.

BackgroundProstaglandin (PG) D2 is the most abundant prostaglandin in the mammalian brain. The physiological and pharmacological actions of PGD2 in the central nervous system seem to be associated with some of the symptoms exhibited by patients with major depressive disorder. Previous studies have found that PGD2 synthase was decreased in the cerebrospinal fluid of major depressive disorder patients. We speculated that there may be a dysregulation of PGD2 levels in major depressive disorder.MethodsUltra-performance liquid chromatography-tandem mass spectrometry coupled with a stable isotopic-labeled internal standard was used to determine PGD2 levels in the plasma of major depressive disorder patients and in the brains of depressive mice. A total of 32 drug-free major depressive disorder patients and 30 healthy controls were recruited. An animal model of depression was constructed by exposing mice to 5 weeks of chronic unpredictable mild stress. To explore the role of PGD2 in major depressive disorder, selenium tetrachloride was administered to simulate the change in PGD2 levels in mice.ResultsMice exposed to chronic unpredictable mild stress exhibited depression-like behaviors, as indicated by reduced sucrose preference and increased immobility time in the forced swimming test. PGD2 levels in the plasma of major depressive disorder patients and in the brains of depressive mice were both decreased compared with their corresponding controls. Further inhibiting PGD2 production in mice resulted in an increased immobility time in the forced swimming test that could be reversed by imipramine.ConclusionDecreased PGD2 levels in major depressive disorder are associated with depression-like behaviors.

Synthesis and characterization of Se nanostructures via co-precipitation, hydrothermal, microwave and sonochemical routes using novel starting reagents for solar cells

Herein, selenium (Se) products were successfully synthesized via four different synthesis routes, co-precipitation, hydrothermal, microwave and sonochemical routes, involving selenium tetrachloride as a selenium source and hydrazine, potassium borohydride, and thioglycolic acid (TGA) as reducing reagents. TGA can be easily oxidized to the corresponding disulfide [SCH2CO2H]2, which can reduce SeCl4 to Se. To our knowledge, it is the first time that TGA was used as reducing agent for the synthesis of Se nanostructures. The obtained Se was characterized by XRD, SEM, EDS, and DRS. Furthermore, the effects of the reducing agent as well as solvent, NaOH and type of preparation method on the morphology and particle size of the products were investigated. Selenium thin film was deposited on the FTO–TiO2 by Dr-blading technique and it was utilized into solar cell and measured open circuit voltage (Voc), short circuit current (Jsc), and fill factor (FF). The studies showed that preparation method play crucial role on particles morphology and size. Accordingly various efficiencies of obtained nanostructures will be achieved for solar cell applications.

Facile microwave synthesis, characterization, and solar cell application of selenium nanoparticles

In the current study, selenium (Se) nanoparticles with hexagonal phase were synthesized by applying microwave irradiation using selenium tetrachloride as a starting reagent in distilled water at various conditions. Se nanoparticles were formed using hydrazine in short reaction time (4min). The effects of reaction time, irradiation power, and types of surfactant including sodium dodecyl sulfate (SDS), polyethylene glycol 600 (PEG 600), and cetyltrimethylammonium bromide (CTAB) on the particle size of the product were investigated. To fabricate a FTO/TiO2/Se/Pt-FTO and FTO/Se/CdS/Pt-FTO solar cell, selenium film was directly deposited on top of the TiO2 and FTO glass prepared by Doctor’s blade method, respectively. Solar cell results indicate that an inexpensive solar cell could be developed by synthesis of Se nanoparticles through microwave method.

ChemInform Abstract: Synthesis of Bis(1,2,2‐trichloroethyl) and Bis(dichlorovinyl) Selenides by Electrophilic Reaction of Selenium Dichloride with 1,2‐Dichloroethylene.

AbstractThe reaction of 1,2‐dichloroethylene (I) with selenium dichloride is studied.

Synthesis and characterization of CuInSe2 nanocrystals via facile microwave approach and study of their behavior in solar cell

Copper indium selenide, CuInSe2, crystals with different morphologies and particle sizes were obtained via a simple microwave reaction among different copper precursors, indium chloride (InCl3) and selenium tetrachloride (SeCl4). The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible (UV–vis) spectroscopy, and photoluminescence (PL) spectroscopy. The effect of copper precursor, microwave time, and power on the particle size and morphology has been investigated. The band gap of CuInSe2 nanoparticles was calculated by UV–vis and PL spectrum. The thin film of CIS nanoparticles and solar cell were fabricated and characterized by I–V curve.

Synthesis of bis(1,2,2-trichloroethyl) and bis(dichlorovinyl) selenides by electrophilic reaction of selenium dichloride with 1,2-dichloroethylene

Electrophilic reactions of sulfur dichloride with unsaturated systems underlie one of the most general methods for the synthesis of bis(2-chloroalkyl) sulfides [1]. Reactions of analogous unsaturated compounds with selenium tetrachloride yield the corresponding bis-adducts containing a four-coordinate selenium atom (>SeCl2) [2]. In recent years we performed systematic studies on reactions of SeCl2 with alkenes and their oxygenand sulfur-containing derivatives [3, 4]. Reactions with chlorinated ethylenes, such as chloroethene, 1,1and 1,2-dichloroethenes, and trichloroethene were reported only for SCl2, and they required the presence of Lewis acids as catalyst [5]. Garratt et al. [6] showed that SeCl4 failed to react with 1,2-dichloroethene in the presence of AlCl3 as catalyst. Nevertheless, we succeeded in adding SeCl2 to bis(2-chlorovinyl) selenide (a selenium-containing derivative of 1,2-dichloroethene) in the absence of a catalyst [7]. Sulfur and selenium dichlorides are known to act as chlorinating agents toward alkylsulfanyl derivatives of polychloroethenes, e.g., alkyl 2,2-dichlorovinyl sulfides [8].

ChemInform Abstract: Regioselective Addition of Sulfur Dichloride and Selenium Tetrachloride to Diallyldimethylsilane as the Method of Preparation of Eight‐Membered Heterocycles Containing Silicon and Chalcogens.

AbstractThe electrophilic addition of SCl2 or SeCl4 to diallylsilane (I) proceeds strictly according to the Markovnikoff rule furnishing previously unknown thiasilacyclooctane (II) or selenasilaoctane (III), respectively.

Synthesis and Reactivity of Divinylselenium Dichlorides and Dibromides

Regio- and stereospecific electrophilic addition reactions of selenium tetrachloride and selenium tetrabromide to propargyl alcohols are reported. (Z,Z)-Bis(β-chlorovinyl)selenium dichlorides were isolated in high yields, and their reactivity was dependent on their substitution pattern. Products derived from unsubstituted, α-methyl-, or α,α-dimethylpropargyl alcohols readily underwent transfer of chlorine atoms to one of the two double bonds. (Z,Z)-Bis(β-chlorovinyl)selenium dichlorides derived from γ-phenyl- or γ-isopropenylpropargyl alcohols underwent cyclization to form benzoselenophene derivatives; this was accompanied by the formation of the corresponding dichloro-substituted allylic alcohols. In contrast, selenium tetrachloride reacts with γ-phenylpropargyl alcohol exclusively as a chlorinating agent, giving (3-chloroprop-1-yn-1-yl)benzene quantitatively. Products of regio- and stereospecific electrophilic addition of selenium tetrabromide are also described. Reaction mechanisms are proposed.

ChemInform Abstract: Synthesis of a New Four‐Membered Heterocycle by Reaction of Selenium Dichloride with Divinyl Sulfone.

Selenium dichloride and dibromide were not isolated as individual substances. It is known that selenium dichloride in solution exists in equilibrium with selenium tetrachloride and Se2Cl2, whereas the equilibrium of selenium dibromide in solution involves Se2Br2 and bromine [1, 2]. We were the first to reveal that freshly prepared selenium dichloride and selenium dibromide can be used in selective synthesis of organic selenides [3, 4]. Reactions of selenium dichloride and dibromide with divinyl chalcogenides and their derivatives opened a synthetic route to new heterocyclic compounds [5–10]. In continuation of our systematic studies on the chemical properties of selenium dihalides [3–10], we examined previously unknown addition of selenium dichloride to divinyl sulfone. It was found that the reaction occurs with high regioselectivity and leads to the formation of a new four-membered heterocyclic compound, 2,4-bis(chloromethyl)-1,3-thiaselenetane 1,1-dioxide (I). The yield of compound I was 85%, calculated on the reacted divinyl sulfone, the conversion of the latter being 58%. sional correlation techniques, as well as by mass spectrometry and elemental analysis. According to the NMR data, compound I was isolated as a mixture of two diastereoisomers at a ratio of 2.5 : 1. 2,4-Bis(chloromethyl)-1,3-thiaselenetane 1,1-dioxide (I). mp 76–77°C. Major diastereoisomer: H NMR spectrum, δ, ppm: 3.91 d.d (2H, CH2Cl, J = 11.8, J = 7.1 Hz), 4.27 d.d (2H, CH2Cl, J = 11.8, J = 7.1 Hz), 5.52 d.d (2H, CHSe, J = 7.1, 7.1 Hz). C NMR spectrum, δC, ppm: 41.39 (CH2Cl), 69.36 (CHSe). Se NMR spectrum: δSe 193 ppm. Minor diastereoisomer: H NMR spectrum, δ, ppm: 3.93 d.d (2H, CH2Cl, J = 11.9, J = 7.7 Hz), 4.31 d.d (2H, CH2Cl, J = 11.9, J = 7.9 Hz), 5.54 d.d (2H, CHSe, J = 7.7, 7.9 Hz). C NMR spectrum, δC, ppm: 41.63 (CH2Cl) , 70.03 (CHSe) . Se NMR spectrum: δSe 200 ppm. Mass spectrum, m/z (Irel, %): 268 (29) [M], 204 (12), 169 (100), 142 (56), 133 (34), 107 (82), 93 (24), 81 (13), 61 (19), 53 (21). Found, %: C 17.69; H 2.21; Cl 26.30. C4H6O2Cl2SSe. Calculated, %: C 17.93; H 2.26; Cl 26.46. The NMR spectra were recorded from solutions in CDCl3 on a Bruker DPX-400 instrument at 400.13 (H, HMDS), 100.61 (C, HMDS), and 76.30 MHz (Se, Me2Se). The mass spectrum (electron impact, 70 eV) was obtained on a Shimadzu GCMS-QP5050A instrument. This study was performed in the framework of the Basic Research Program of the Russian Academy of Sciences (project no. 5.1.8).

Synthesis of a new four-membered heterocycle by reaction of selenium dichloride with divinyl sulfone

Selenium dichloride and dibromide were not isolated as individual substances. It is known that selenium dichloride in solution exists in equilibrium with selenium tetrachloride and Se2Cl2, whereas the equilibrium of selenium dibromide in solution involves Se2Br2 and bromine [1, 2]. We were the first to reveal that freshly prepared selenium dichloride and selenium dibromide can be used in selective synthesis of organic selenides [3, 4]. Reactions of selenium dichloride and dibromide with divinyl chalcogenides and their derivatives opened a synthetic route to new heterocyclic compounds [5–10]. In continuation of our systematic studies on the chemical properties of selenium dihalides [3–10], we examined previously unknown addition of selenium dichloride to divinyl sulfone. It was found that the reaction occurs with high regioselectivity and leads to the formation of a new four-membered heterocyclic compound, 2,4-bis(chloromethyl)-1,3-thiaselenetane 1,1-dioxide (I). The yield of compound I was 85%, calculated on the reacted divinyl sulfone, the conversion of the latter being 58%. sional correlation techniques, as well as by mass spectrometry and elemental analysis. According to the NMR data, compound I was isolated as a mixture of two diastereoisomers at a ratio of 2.5 : 1. 2,4-Bis(chloromethyl)-1,3-thiaselenetane 1,1-dioxide (I). mp 76–77°C. Major diastereoisomer: H NMR spectrum, δ, ppm: 3.91 d.d (2H, CH2Cl, J = 11.8, J = 7.1 Hz), 4.27 d.d (2H, CH2Cl, J = 11.8, J = 7.1 Hz), 5.52 d.d (2H, CHSe, J = 7.1, 7.1 Hz). C NMR spectrum, δC, ppm: 41.39 (CH2Cl), 69.36 (CHSe). Se NMR spectrum: δSe 193 ppm. Minor diastereoisomer: H NMR spectrum, δ, ppm: 3.93 d.d (2H, CH2Cl, J = 11.9, J = 7.7 Hz), 4.31 d.d (2H, CH2Cl, J = 11.9, J = 7.9 Hz), 5.54 d.d (2H, CHSe, J = 7.7, 7.9 Hz). C NMR spectrum, δC, ppm: 41.63 (CH2Cl) , 70.03 (CHSe) . Se NMR spectrum: δSe 200 ppm. Mass spectrum, m/z (Irel, %): 268 (29) [M], 204 (12), 169 (100), 142 (56), 133 (34), 107 (82), 93 (24), 81 (13), 61 (19), 53 (21). Found, %: C 17.69; H 2.21; Cl 26.30. C4H6O2Cl2SSe. Calculated, %: C 17.93; H 2.26; Cl 26.46. The NMR spectra were recorded from solutions in CDCl3 on a Bruker DPX-400 instrument at 400.13 (H, HMDS), 100.61 (C, HMDS), and 76.30 MHz (Se, Me2Se). The mass spectrum (electron impact, 70 eV) was obtained on a Shimadzu GCMS-QP5050A instrument. This study was performed in the framework of the Basic Research Program of the Russian Academy of Sciences (project no. 5.1.8).

Reaction of divinyl sulfide with selenium tetrachloride

Divinyl sulfide is a multipurpose product in modern organic synthesis [1]; various heterocyclic compounds were obtained on its basis [2]. Earlier, we have studied the reactions of divinyl sulfide with selenium dichloride and dibromide, which, when carried out at room temperature in chloroform, result in 5-halo-2halomethyl-1,3-thiaselenolanes, whereas in CCl4, in 2,6-dihalo-1,4-thiaselenanes [3–6].

5-Selenization of salicylic acid derivatives yielded isoform-specific 5-lipoxygenase inhibitors

Low molecular weight seleno-organic compounds exhibit glutathione peroxidase (GPx)-like activity; the well-known compound ebselen is being used in clinical trials as a stroke medication. Here, we describe the facile one-step synthesis of novel 5-selenized salicylic acid derivatives using selenium tetrachloride. The products were analyzed by spectroscopic studies including (77)Se-NMR and some were subjected to X-ray structure determination. Several products were identified as selective inhibitors of the pro-inflammatory 5-lipoxygenase (LOX) but had little effect on the catalytic activity of 12/15-LOX, which has been implicated in the synthesis of anti-inflammatory mediators. Such isoform-specificity (specificity coefficient >120) has not been reported before for any seleno-organic compound. In addition, synthesis products exhibited GPx-like activity, which was higher than that of ebselen for some derivatives.

First example of aromatic electrophilic substitution using selenium(II) chloride

Selenium dichloride is a promising reagent for organic synthesis. However, prior to our studies [1, 2], it was not used for the preparation of organoselenium compounds. It is known that selenium dichloride in solution exists in equilibrium with selenium tetrachloride and Se2Cl2 [3]. No examples of aromatic electrophilic substitution with participation of selenium dihalides have been reported so far. While continuing our systematic studies on reactions of selenium dihalides [1, 2, 4–10], we examined the reaction of selenium dichloride with methoxybenzene. The reaction occurred as aromatic replacement of hydrogen by the electrophile Se and afforded bis(4-methoxyphenyl) selenide (I) in high yield (91%). Thus selenium dichloride may be used as source of electrophilic Se species in aromatic electrophilic substitution reactions. The possibility of using selenium dihalides for performing analogous reactions with other aromatic systems is now under study. Bis(4-methoxyphenyl) selenide (I). mp 54–55°C; published data [11]: mp 54°C. H NMR spectrum, δ, ppm: 7.28 d (4H, CH, J = 7.4 Hz), 6.69 d (4H, CH, J = 7.4 Hz), 3.72 s (6H, CH3O). C NMR spectrum, δC, ppm: 158.85 (C), 135.24 (C), 122.04 (C), 114.53 (C), 54.49 (CH3O). Mass spectrum, m/z (Irel, %): 294 [M] (75), 214 (100), 199 (96), 187 (14), 171 (28), 144 (12), 128 (25), 107 (77), 92 (13), 77 (14), 63 (47), 39 (18). The H and C NMR spectra were recorded on a Bruker DPX-400 spectrometer at 400.13 and 100.61 MHz, respectively, from a solution in carbon tetrachloride; the chemical shifts were determined relative to hexamethyldisiloxane. The mass spectrum (electron impact, 70 eV) was obtained on a Shimadzu GCMS-QP5050A instrument.