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Grzegorz Mloston - One of the best experts on this subject based on the ideXlab platform.
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the fluoride anion catalyzed sulfurization of Thioketones with elemental sulfur leading to sulfur rich heterocycles first sulfurization of thiochalcones
Molecules, 2021Co-Authors: Grzegorz Mloston, Katarzyna Urbaniak, Jakub Wreczycki, Dariusz Bielinski, Heinz HeimgartnerAbstract:Fluoride anion was demonstrated as a superior activator of elemental sulfur (S8) to perform sulfurization of Thioketones leading to diverse sulfur-rich heterocycles. Due to solubility problems, reactions must be carried out either in THF using tetrabutylammonium fluoride (TBAF) or in DMF using cesium fluoride (CsF), respectively. The reactive sulfurizing reagents are in situ generated, nucleophilic fluoropolysulfide anions FS(8−x)−, which react with the C=S bond according to the carbophilic addition mode. Dithiiranes formed thereby, existing in an equilibrium with the ring-opened form (diradicals/zwitterions) are key-intermediates, which undergo either a step-wise dimerization to afford 1,2,4,5-tetrathianes or an intramolecular insertion, leading in the case of thioxo derivatives of 2,2,4,4-tetramethylcyclobutane-1,3-dione to ring enlarged products. In reactions catalyzed by TBAF, water bounded to fluoride anion via H-bridges and forming thereby its stable hydrates is involved in secondary reactions leading, e.g., in the case of 2,2,4,4-tetramethyl-3-thioxocyclobutanone to the formation of some unexpected products such as the ring enlarged dithiolactone and ring-opened dithiocarboxylate. In contrast to Thioketones, the fluoride anion catalyzed sulfurization of their α,β-unsaturated analogues, i.e., thiochalcones is slow and inefficient. However, an alternative protocol with triphenylphosphine (PPh3) applied as a catalyst, offers an attractive approach to the synthesis of 3H-1,2-dithioles via 1,5-dipolar electrocyclization of the in situ-generated α,β-unsaturated thiocabonyl S-sulfides. All reactions occur under mild conditions and can be considered as attractive methods for the preparation of sulfur rich heterocycles with diverse ring-size.
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structure of diferrocenyl Thioketone from molecule to crystal
Molecules, 2019Co-Authors: Piotr Matczak, Grzegorz Mloston, Roza Hamerafaldyga, Helmar Gorls, Wolfgang WeigandAbstract:Ferrocenyl-functionalized Thioketones have recently been recognized as useful building blocks for sulfur-containing compounds with potential applications in materials chemistry. This work is devoted to a single representative of such Thioketones, namely diferrocenyl Thioketone (Fc2CS), whose structure has been determined here for the first time. Both X-ray crystallography and a wide variety of quantum-chemical methods were used to explore the structure of Fc2CS. In addition to the X-ray structure determination, intermolecular interactions occurring in the crystal structure of Fc2CS were examined in detail by quantum-chemical methods. These methods were also an invaluable tool in studying the molecular structure of Fc2CS, from the gas phase to solutions and to its crystal. Intramolecular interactions governing the conformational behavior of an isolated Fc2CS molecule were deduced from quantum-chemical analyses carried out in orbital space and real space. Our experimental and theoretical results indicate that the main structural features of an isolated Fc2CS molecule in its lowest-energy geometry are retained both upon solvation and in the crystal. The tilt of ferrocenyl groups is only slightly affected by crystal packing forces that are dominated by dispersion. Nonetheless, a network of intermolecular interactions, such as H···H, C···H and S···H, was detected in the Fc2CS crystal but each of them is fairly weak.
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diferrocenyl Thioketone reactions with bisphosphane pt 0 complexes electrochemical and computational studies
Materials, 2019Co-Authors: Sebastian Grober, Grzegorz Mloston, Piotr Matczak, Helmar Gorls, Slawomir Domagala, Thomas Weisheit, Annika Duver, Wolfgang WeigandAbstract:Diferrocenyl Thioketone reacts smoothly with (bisphosphane)Pt(0) complexes in toluene solution at room temperature yielding 1:1 adducts identified as ferrocenyl (Fc) functionalized platinathiiranes. Their structures were unambiguously confirmed by means of spectroscopic methods as well as by X-ray diffraction analysis. A unique, ferrocene-rich platinathiirane, bearing three Fc-units, was prepared starting with [bis(diphenylphosphino)ferrocene] Pt(0(η2-norbornene). For comparison, a similar platinathiirane with one Fc-unit was obtained from the reaction of the latter complex with thiobenzophenone. Quantum-chemical calculations were carried out to describe the bonding pattern and frontier molecular orbitals of the ferrocene-rich platinathiirane complexes. These calculations confirmed that the C=S bond loses its formally double-bond character upon complexation (bisphosphane)Pt(0). Cyclic voltammetry measurements were performed to characterize the obtained platinathiiranes in CH2Cl2 solutions. For comparison, the cyclic voltammogram for diferrocenyl Thioketoneas a mixed-valent (FeII-FeIII) compound was also recorded and analyzed. The results point out to a diffusion controlled electrode process in case of differocenyl Thioketone and mixed diffusion and adsorption controlled electrode process in the case of the studied platinathiiranes.
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a convenient access to 1 2 diferrocenyl substituted ethylenes via 3 2 cycloelimination of 2 silylated 4 4 5 5 tetrasubstituted 1 3 dithiolanes
Journal of Sulfur Chemistry, 2018Co-Authors: Grzegorz Mloston, Roza Hamerafaldyga, Katarzyna Urbaniak, Wolfgang Weigand, Heinz HeimgartnerAbstract:Ferrocenyl Thioketones bearing a hetaryl, phenyl or alkyl group as the second substituent react with (trimethylsilyl)diazomethane at ca. −30°C in THF solution without formation of a stable [3 + 2]-...
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a novel application of 2 silylated 1 3 dithiolanes for the synthesis of aryl hetaryl substituted ethenes and dibenzofulvenes
Beilstein Journal of Organic Chemistry, 2017Co-Authors: Grzegorz Mloston, Paulina Pipiak, Roza Hamerafaldyga, Heinz HeimgartnerAbstract:Trimethylsilyldiazomethane (TMS-CHN2) reacts readily with hetaryl Thioketones to give sterically crowded 2-trimethylsilyl-4,4,5,5-tetrahetaryl-1,3-dithiolanes with complete regioselectivity at −75 °C as well as at rt. Thiofluorenone, a relatively stable and highly reactive aryl Thioketone, yields upon treatment with TMS-CHN2 at −60 °C the corresponding 1,3,4-thiadiazoline. This unstable cycloadduct undergoes decomposition at ca. −45 °C and the silylated thiocarbonyl S-methanide generated thereby is trapped with complete regioselectivity by aryl or hetaryl Thioketones forming also sterically crowded 2-trimethylsilyl-1,3-dithiolanes. The obtained 1,3-dithiolanes, by treatment with an equimolar amount of TBAF in a one-pot procedure, are converted in high yields into hetaryl/aryl-substituted ethenes or dibenzofulvenes, respectively, via a cycloreversion reaction of the intermediate 1,3-dithiolane carbanion. The presented protocol offers a new, highly efficient approach to tetrasubstituted ethenes and dibenzofulvenes bearing aryl and/or hetaryl substituents.
Heinz Heimgartner - One of the best experts on this subject based on the ideXlab platform.
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the fluoride anion catalyzed sulfurization of Thioketones with elemental sulfur leading to sulfur rich heterocycles first sulfurization of thiochalcones
Molecules, 2021Co-Authors: Grzegorz Mloston, Katarzyna Urbaniak, Jakub Wreczycki, Dariusz Bielinski, Heinz HeimgartnerAbstract:Fluoride anion was demonstrated as a superior activator of elemental sulfur (S8) to perform sulfurization of Thioketones leading to diverse sulfur-rich heterocycles. Due to solubility problems, reactions must be carried out either in THF using tetrabutylammonium fluoride (TBAF) or in DMF using cesium fluoride (CsF), respectively. The reactive sulfurizing reagents are in situ generated, nucleophilic fluoropolysulfide anions FS(8−x)−, which react with the C=S bond according to the carbophilic addition mode. Dithiiranes formed thereby, existing in an equilibrium with the ring-opened form (diradicals/zwitterions) are key-intermediates, which undergo either a step-wise dimerization to afford 1,2,4,5-tetrathianes or an intramolecular insertion, leading in the case of thioxo derivatives of 2,2,4,4-tetramethylcyclobutane-1,3-dione to ring enlarged products. In reactions catalyzed by TBAF, water bounded to fluoride anion via H-bridges and forming thereby its stable hydrates is involved in secondary reactions leading, e.g., in the case of 2,2,4,4-tetramethyl-3-thioxocyclobutanone to the formation of some unexpected products such as the ring enlarged dithiolactone and ring-opened dithiocarboxylate. In contrast to Thioketones, the fluoride anion catalyzed sulfurization of their α,β-unsaturated analogues, i.e., thiochalcones is slow and inefficient. However, an alternative protocol with triphenylphosphine (PPh3) applied as a catalyst, offers an attractive approach to the synthesis of 3H-1,2-dithioles via 1,5-dipolar electrocyclization of the in situ-generated α,β-unsaturated thiocabonyl S-sulfides. All reactions occur under mild conditions and can be considered as attractive methods for the preparation of sulfur rich heterocycles with diverse ring-size.
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a convenient access to 1 2 diferrocenyl substituted ethylenes via 3 2 cycloelimination of 2 silylated 4 4 5 5 tetrasubstituted 1 3 dithiolanes
Journal of Sulfur Chemistry, 2018Co-Authors: Grzegorz Mloston, Roza Hamerafaldyga, Katarzyna Urbaniak, Wolfgang Weigand, Heinz HeimgartnerAbstract:Ferrocenyl Thioketones bearing a hetaryl, phenyl or alkyl group as the second substituent react with (trimethylsilyl)diazomethane at ca. −30°C in THF solution without formation of a stable [3 + 2]-...
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a novel application of 2 silylated 1 3 dithiolanes for the synthesis of aryl hetaryl substituted ethenes and dibenzofulvenes
Beilstein Journal of Organic Chemistry, 2017Co-Authors: Grzegorz Mloston, Paulina Pipiak, Roza Hamerafaldyga, Heinz HeimgartnerAbstract:Trimethylsilyldiazomethane (TMS-CHN2) reacts readily with hetaryl Thioketones to give sterically crowded 2-trimethylsilyl-4,4,5,5-tetrahetaryl-1,3-dithiolanes with complete regioselectivity at −75 °C as well as at rt. Thiofluorenone, a relatively stable and highly reactive aryl Thioketone, yields upon treatment with TMS-CHN2 at −60 °C the corresponding 1,3,4-thiadiazoline. This unstable cycloadduct undergoes decomposition at ca. −45 °C and the silylated thiocarbonyl S-methanide generated thereby is trapped with complete regioselectivity by aryl or hetaryl Thioketones forming also sterically crowded 2-trimethylsilyl-1,3-dithiolanes. The obtained 1,3-dithiolanes, by treatment with an equimolar amount of TBAF in a one-pot procedure, are converted in high yields into hetaryl/aryl-substituted ethenes or dibenzofulvenes, respectively, via a cycloreversion reaction of the intermediate 1,3-dithiolane carbanion. The presented protocol offers a new, highly efficient approach to tetrasubstituted ethenes and dibenzofulvenes bearing aryl and/or hetaryl substituents.
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generation and reactions of thiocarbonyl s 2 2 2 trifluoroethanides synthesis of trifluoromethylated 1 3 dithiolanes thiiranes and alkenes
Journal of Fluorine Chemistry, 2017Co-Authors: Marcin K Kowalski, Grzegorz Mloston, Emilia Obijalska, Heinz HeimgartnerAbstract:Abstract The ‘in situ’ generated 1,1,1-trifluorodiazoethane reacts with Thioketones as C=S dipolarophiles in a two-phase system (DCM/H2O) at room temperature to yield trifluoromethylated 2,5-dihydro-1,3,4-thiadiazoles. Whereas stable crystalline products were obtained with cyclobutanethiones, the reaction with aromatic and heteroaromatic Thioketones occured with spontaneous elimination of nitrogen. The formation of sterically crowded 4,4,5,5-tetrahetaryl-1,3-dithiolanes indicates that thiocarbonyl S-methanides are formed immediately and entered formal [3+2]-cycloaddition as diradical species with the starting Thioketone. A protocol for the preparation of 3,3,3-trifluoropropene derivatives starting from corresponding Thioketones and 1,1,1-trifluorodiazoethane is also presented.
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Dimerization reactions of aryl selenophen-2-yl-substituted thiocarbonyl S-methanides as diradical processes: a computational study
Beilstein journal of organic chemistry, 2017Co-Authors: Michael L. Mckee, Katarzyna Urbaniak, Grzegorz Mloston, Heinz HeimgartnerAbstract:An intriguing stepwise diradical mechanism of the dimerization of the reactive intermediate (thiocarbonyl S-methanide) appearing in the reaction of phenyl selenophen-2-yl Thioketone with diazomethane was studied by means of computational methods. The preferred formation of the unusual macroheterocycle, competitive with the 1,3-ring closure leading to a thiirane and the head-to-head dimerization yielding a 1,4-dithiane derivative, respectively, was explained based on the analysis of the structure of the favored conformer of the intermediate, delocalized diradical species. The influence of selenium as a ‘heavy atom’ for stabilization of this intermediate has been emphasized.
Heimgartner Heinz - One of the best experts on this subject based on the ideXlab platform.
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The [4+2]‐Cycloaddition of α‐Nitrosoalkenes with Thiochalcones as a Prototype of Periselective Hetero‐Diels–Alder Reactions—Experimental and Computational Studies
2020Co-Authors: Mlostoń Grzegorz, Heimgartner Heinz, Urbaniak Katarzyna, Jasiński Marcin, Würthwein Ernst‐ulrich, Zimmer Reinhold, Reissig Hans‐ulrichAbstract:The [4+2]‐cycloadditions of α‐nitrosoalkenes with thiochalcones occur with high selectivity at the Thioketone moiety of the dienophile providing styryl‐substituted 4H‐1,5,2‐oxathiazines in moderate to good yields. Of the eight conceivable hetero‐Diels–Alder adducts only this isomer was observed, thus a prototype of a highly periselective and regioselective cycloaddition has been identified. Analysis of crude product mixtures revealed that the α‐nitrosoalkene also adds competitively to the Thioketone moiety of the thiochalcone dimer affording bis‐heterocyclic [4+2]‐cycloadducts. The experiments are supported by high‐level DFT calculations that were also extended to related hetero‐Diels–Alder reactions of other nitroso compounds and Thioketones. These calculations reveal that the title cycloadditions are kinetically controlled processes confirming the role of Thioketones as superdienophiles. The computational study was also applied to the experimentally studied thiochalcone dimerization, and showed that the 1,2‐dithiin and 2H‐thiopyran isomers are in equilibrium with the monomer. Again, the DFT calculations indicate kinetic control of this process
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Hetero-Diels-Alder Reactions of α-Nitrosoalkenes with Ferrocenyl, Hetaryl and Cycloaliphatic Thioketones
Wiley-Blackwell Publishing Inc., 2018Co-Authors: Mlostoń Grzegorz, Urbaniak Katarzyna, Zimmer Reinhol, Reissig Hans-ulrich, Heimgartner HeinzAbstract:The in situ generated α-nitrosoalkenes react with ferrocenyl, hetaryl and cycloaliphatic Thioketones yielding 4H-1,5,2-oxa- thiazines as products of the hetero-Diels-Alder reaction. These products are formed in a perfect regioselective manner. A similar reactivity is displayed by a thiochalcone (1,3-diphenylprop-2-ene-1-thione), and in that case, the [4 + 2]-cyclo-addition occurs also chemoselectively and regioselectively along the C=S bond acting as a heterodienophile. The stability of the 4H-1,5,2-oxathiazines depends on the type of substituents, and in the case of ferrocenyl Thioketones, the diferrocenyl representative is the reagent of choice. The replacement of one ferrocenyl group by an ethyl group leads to a dramatic decrease of the product stability. Sterically crowded cycloaliphatic Thioketones derived from 2,2,4,4-tetramethylcyclobutane-1,3-dione are exceptional dienophiles in reactions with trifluoromethyl-substituted nitrosoalkenes, and in these cases, a remarkably stable 3-trifluoromethyl-4H-1,5,2-oxathiazine derivative was obtained. For the first time, perfectly stable and non-odorous 2,2,4,4- tetramethylcyclobutane-1,3-dithione was explored as an active heterodienophile for a two-fold hetero-Diels-Alder reaction
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A convenient access to 1,2-diferrocenyl-substituted ethylenes via [3 + 2]-cycloelimination of 2-silylated 4,4,5,5-tetrasubstituted 1,3-dithiolanes
Taylor & Francis, 2018Co-Authors: Mlostoń Grzegorz, Hamera-faldyga Roza, Urbaniak Katarzyna, Weigand Wolfgang, Heimgartner HeinzAbstract:Ferrocenyl Thioketones bearing a hetaryl, phenyl or alkyl group as the second substituent react with (trimethylsilyl)diazomethane at ca. −30°C in THF solution without formation of a stable [3+2]-cycloadduct. After the spontaneous evolution of N2, the corresponding sterically crowded 4,4,5,5-tetrasubstituted 2-silylated 1,3-dithiolanes are formed as products of the second [3 + 2]-cycloaddition of the intermediate thiocarbonyl S-methanide with the starting Thioketone. After desilylation by treatment with TBAF, they are converted into the corresponding carbanions, which display different stability depending on the type of substituent. The presence of hetaryl and phenyl groups results in the exclusive formation of 1,2- diferrocenyl ethylenes. In contrast, the presence of methyl groups significantly enhances the stability of the carbanion, which by protonation yields trans-4,5-diferrocenyl-4,5-dimethyl-1,3-dithiolane
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Silylated thiocarbonyl S-methanides as key intermediates in one-pot olefination reactions leading to ferrocenyl-substituted ethenes and dibenzofulvenes
Taylor & Francis, 2018Co-Authors: Mlostoń Grzegorz, Hamera-faldyga Roza, Heimgartner HeinzAbstract:(Trimethylsilyl)diazomethane (TMS-CHN2) reacts smoothly with cycloaliphatic Thioketones as well as with fluorene-9-thione at low temperature to give the corresponding 1,3,4-thiadiazole derivatives as product of a regioselective [3+2]-cycloaddition. In the first case, the obtained cycloadducts are relatively stable and eliminate N2 upon heating at 40ºC. In the second case, N2-extrusion occurs already at –40ºC. The silylated thiocarbonyl S-methanides generated thereby can be trapped regioselectively with ferrocenyl hetaryl Thioketones to give the sterically crowded 2-silylated 4,4,5,5-tetrasubstituted 1,3-dithiolanes. Without isolation, these products are desilylated with TBAF and tetrasubstituted ethenes or dibenzofulvenes are obtained as final products via cycloelimination (‘[3+2]-cycloreversion’) of the intermediate 1,3-dithiolane carbanion
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Synthesis of ferrocenyl Thioketones and their reactions with diphenyldiazomethane
Taylor & Francis, 2015Co-Authors: Mlostoń Grzegorz, Hamera Roza, Heimgartner HeinzAbstract:A series of ferrocenyl ketones was obtained via Friedel-Crafts acylation with mixed anhydrides using ferrocene as a nucleophilic agent or ferrocene carboxylic acid as a precursor of the electrophilic species. The ketones obtained thereby undergo smooth thionation (THF, 65 ºC) with Lawesson’s reagent. The ferrocenyl Thioketones react with diphenyldiazomethane via N2 elimination to afford the hitherto unknown ferrocenyl-substituted thiiranes
Roza Hamerafaldyga - One of the best experts on this subject based on the ideXlab platform.
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structure of diferrocenyl Thioketone from molecule to crystal
Molecules, 2019Co-Authors: Piotr Matczak, Grzegorz Mloston, Roza Hamerafaldyga, Helmar Gorls, Wolfgang WeigandAbstract:Ferrocenyl-functionalized Thioketones have recently been recognized as useful building blocks for sulfur-containing compounds with potential applications in materials chemistry. This work is devoted to a single representative of such Thioketones, namely diferrocenyl Thioketone (Fc2CS), whose structure has been determined here for the first time. Both X-ray crystallography and a wide variety of quantum-chemical methods were used to explore the structure of Fc2CS. In addition to the X-ray structure determination, intermolecular interactions occurring in the crystal structure of Fc2CS were examined in detail by quantum-chemical methods. These methods were also an invaluable tool in studying the molecular structure of Fc2CS, from the gas phase to solutions and to its crystal. Intramolecular interactions governing the conformational behavior of an isolated Fc2CS molecule were deduced from quantum-chemical analyses carried out in orbital space and real space. Our experimental and theoretical results indicate that the main structural features of an isolated Fc2CS molecule in its lowest-energy geometry are retained both upon solvation and in the crystal. The tilt of ferrocenyl groups is only slightly affected by crystal packing forces that are dominated by dispersion. Nonetheless, a network of intermolecular interactions, such as H···H, C···H and S···H, was detected in the Fc2CS crystal but each of them is fairly weak.
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a convenient access to 1 2 diferrocenyl substituted ethylenes via 3 2 cycloelimination of 2 silylated 4 4 5 5 tetrasubstituted 1 3 dithiolanes
Journal of Sulfur Chemistry, 2018Co-Authors: Grzegorz Mloston, Roza Hamerafaldyga, Katarzyna Urbaniak, Wolfgang Weigand, Heinz HeimgartnerAbstract:Ferrocenyl Thioketones bearing a hetaryl, phenyl or alkyl group as the second substituent react with (trimethylsilyl)diazomethane at ca. −30°C in THF solution without formation of a stable [3 + 2]-...
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a novel application of 2 silylated 1 3 dithiolanes for the synthesis of aryl hetaryl substituted ethenes and dibenzofulvenes
Beilstein Journal of Organic Chemistry, 2017Co-Authors: Grzegorz Mloston, Paulina Pipiak, Roza Hamerafaldyga, Heinz HeimgartnerAbstract:Trimethylsilyldiazomethane (TMS-CHN2) reacts readily with hetaryl Thioketones to give sterically crowded 2-trimethylsilyl-4,4,5,5-tetrahetaryl-1,3-dithiolanes with complete regioselectivity at −75 °C as well as at rt. Thiofluorenone, a relatively stable and highly reactive aryl Thioketone, yields upon treatment with TMS-CHN2 at −60 °C the corresponding 1,3,4-thiadiazoline. This unstable cycloadduct undergoes decomposition at ca. −45 °C and the silylated thiocarbonyl S-methanide generated thereby is trapped with complete regioselectivity by aryl or hetaryl Thioketones forming also sterically crowded 2-trimethylsilyl-1,3-dithiolanes. The obtained 1,3-dithiolanes, by treatment with an equimolar amount of TBAF in a one-pot procedure, are converted in high yields into hetaryl/aryl-substituted ethenes or dibenzofulvenes, respectively, via a cycloreversion reaction of the intermediate 1,3-dithiolane carbanion. The presented protocol offers a new, highly efficient approach to tetrasubstituted ethenes and dibenzofulvenes bearing aryl and/or hetaryl substituents.
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synthesis of ferrocenyl substituted 1 3 dithiolanes via 3 2 cycloadditions of ferrocenyl hetaryl Thioketones with thiocarbonyl s methanides
Beilstein Journal of Organic Chemistry, 2016Co-Authors: Grzegorz Mloston, Anthony Linden, Roza Hamerafaldyga, Heinz HeimgartnerAbstract:Ferrocenyl hetaryl Thioketones react smoothly with in situ generated thiocarbonyl S-methanides to give 1,3-dithiolanes. In the case of aromatic S-methanides, the sterically more crowded 4,4,5,5-tetrasubstituted 1,3-dithiolanes (2-CH2 isomers) were formed as sole products. The reactions with cycloaliphatic S-methanides led to mixtures of 2-CH2 and 5-CH2 isomers with the major component being the sterically more crowded 2-CH2 isomers. The preferred formation of the latter products is explained by the assumption that the formal [3 + 2]-cycloadducts were formed via a stepwise reaction mechanism with a stabilized 1,5-diradical as a key intermediate. The complete change of the reaction mechanism toward the concerted [3 + 2]-cycloaddition was observed in the reaction of a sterically crowded cycloaliphatic thiocarbonyl ylide with ferrocenyl methyl Thioketone.
Wolfgang Weigand - One of the best experts on this subject based on the ideXlab platform.
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structure of diferrocenyl Thioketone from molecule to crystal
Molecules, 2019Co-Authors: Piotr Matczak, Grzegorz Mloston, Roza Hamerafaldyga, Helmar Gorls, Wolfgang WeigandAbstract:Ferrocenyl-functionalized Thioketones have recently been recognized as useful building blocks for sulfur-containing compounds with potential applications in materials chemistry. This work is devoted to a single representative of such Thioketones, namely diferrocenyl Thioketone (Fc2CS), whose structure has been determined here for the first time. Both X-ray crystallography and a wide variety of quantum-chemical methods were used to explore the structure of Fc2CS. In addition to the X-ray structure determination, intermolecular interactions occurring in the crystal structure of Fc2CS were examined in detail by quantum-chemical methods. These methods were also an invaluable tool in studying the molecular structure of Fc2CS, from the gas phase to solutions and to its crystal. Intramolecular interactions governing the conformational behavior of an isolated Fc2CS molecule were deduced from quantum-chemical analyses carried out in orbital space and real space. Our experimental and theoretical results indicate that the main structural features of an isolated Fc2CS molecule in its lowest-energy geometry are retained both upon solvation and in the crystal. The tilt of ferrocenyl groups is only slightly affected by crystal packing forces that are dominated by dispersion. Nonetheless, a network of intermolecular interactions, such as H···H, C···H and S···H, was detected in the Fc2CS crystal but each of them is fairly weak.
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diferrocenyl Thioketone reactions with bisphosphane pt 0 complexes electrochemical and computational studies
Materials, 2019Co-Authors: Sebastian Grober, Grzegorz Mloston, Piotr Matczak, Helmar Gorls, Slawomir Domagala, Thomas Weisheit, Annika Duver, Wolfgang WeigandAbstract:Diferrocenyl Thioketone reacts smoothly with (bisphosphane)Pt(0) complexes in toluene solution at room temperature yielding 1:1 adducts identified as ferrocenyl (Fc) functionalized platinathiiranes. Their structures were unambiguously confirmed by means of spectroscopic methods as well as by X-ray diffraction analysis. A unique, ferrocene-rich platinathiirane, bearing three Fc-units, was prepared starting with [bis(diphenylphosphino)ferrocene] Pt(0(η2-norbornene). For comparison, a similar platinathiirane with one Fc-unit was obtained from the reaction of the latter complex with thiobenzophenone. Quantum-chemical calculations were carried out to describe the bonding pattern and frontier molecular orbitals of the ferrocene-rich platinathiirane complexes. These calculations confirmed that the C=S bond loses its formally double-bond character upon complexation (bisphosphane)Pt(0). Cyclic voltammetry measurements were performed to characterize the obtained platinathiiranes in CH2Cl2 solutions. For comparison, the cyclic voltammogram for diferrocenyl Thioketoneas a mixed-valent (FeII-FeIII) compound was also recorded and analyzed. The results point out to a diffusion controlled electrode process in case of differocenyl Thioketone and mixed diffusion and adsorption controlled electrode process in the case of the studied platinathiiranes.
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a convenient access to 1 2 diferrocenyl substituted ethylenes via 3 2 cycloelimination of 2 silylated 4 4 5 5 tetrasubstituted 1 3 dithiolanes
Journal of Sulfur Chemistry, 2018Co-Authors: Grzegorz Mloston, Roza Hamerafaldyga, Katarzyna Urbaniak, Wolfgang Weigand, Heinz HeimgartnerAbstract:Ferrocenyl Thioketones bearing a hetaryl, phenyl or alkyl group as the second substituent react with (trimethylsilyl)diazomethane at ca. −30°C in THF solution without formation of a stable [3 + 2]-...
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reactions of 1 2 4 trithiolane and its 4 s oxide with diphosphane pt0 complexes
European Journal of Inorganic Chemistry, 2010Co-Authors: Grzegorz Mloston, Helmar Gorls, Thomas Weisheit, Holm Petzold, Silvio Brautigam, Wolfgang WeigandAbstract:Reactions of 1,2,4-trithiolanes with Pt° complexes often proceed via an oxidative addition of the Pt° complex fragment into the S-S bond and subsequent extrusion of a Thioketone molecule by ring contraction. The six-membered intermediate 5a, formed in the course of the reaction of the parent 1,2,4-trithiolane (1a) and Pt° complex 4, was detected by means of low-temperature NMR spectroscopy. Stable derivatives of this type (compounds 9, 11 and 12) were isolated either by using (dppe)Pt° complex 8 or 1,2,4-trithiolane 4-S-oxide (10). The molecular structures of platinum complexes 9, 11 and 12, as well as their unexpected stability, are discussed.
