Szulfonamidszármazékok katalitikus karbonilezésének mechanizmusvizsgálata = Catalytic carbonylation of sulfonamide derivatives. Mechanistic studies

1. N-klór-arénszulfonamidátok légszáraz, vízmentes és rehidratált mintáit tanulmányoztuk IR-spektroszkópiai és pordiffrakciós módszerekkel. Megállapítottuk, hogy a nátriumsók esetében a vízleadás reverzibilis, míg a vízmentes káliumsók levegőn tárolva nem rehidratálódnak. A ?(OH) rezgés tartományán kívül a ?as(SO2) és a ?(SN) sávok is érzékenyek voltak a minták víztartalmára. 2. Tanulmányoztuk a kis térigényű bisz(dimetil-foszfino)-metán és bisz(dietil-foszfino)-metán ligandumokat tartalmazó [Pd2(P-P)2Cl2] komplexek reakcióit arénszulfonil-azidokkal. Megfigyeltük, hogy a sztérikus gátlás mérséklődése a nitrénkomplex képződésére vezető reakció sebességének jelentős növekedését eredményezi, és elmarad az azidkomplexet eredményező mellékreakció, melyet a [Pd2(dppm)2Cl2] dimer szulfonil-azidokkal mutatott reakcióiban tapasztaltunk. 3. A [Pd2(dppm)2Cl2] dimer és benzoil-azidok reakciójával 9 új N-benzoil-nitrénkomplexet állítottunk elő, és jellemeztünk spektroszkópiai és krisztallográfiai módszerekkel. Kimutattuk, hogy a hídhelyzetű imidonitrogénatom és a karbonilszénatom között különösen erős p?-p? kapcsolat alakul ki, mely megakadályozza az N-C(O) kötés körüli szabad rotációt. Kinetikai vizsgálataink során megállapítottuk, hogy a vizsgált reakció követi a Hammett-egyenletet. | 1. The structural features of air dried, water free and rehydrated sodium and potassium N-chloroarenesulfonamidates were studied using IR spectroscopy and powder diffraction methods. It was observed that the water free samples of sodium salts are easily rehydrated when stored in air while the potassium salts are reluctant to absorb water under identical conditions. Beside the ?(OH) region between 3600-2900 cm1, the ?as(SO2) and ?(SN) bands were also sensitive to the water content of the samples. 2. The interaction of arenesulfonyl azides with dimeric palladium complexes incorporating sterically less demanding bis(dimethylphosphino)methane or bis(diethylphosphino)methane ligands was studied. The reduced bulkiness of the bridging ligands was reflected by an increased reaction rate and, as opposed to the reaction of the [Pd2(dppm)2Cl2] dimer with the same reagents, by the lack of a side reaction resulting in azide complexes. 3. Nine N-benzoyl nitrene complexes were synthesized by reacting the [Pd2(dppm)2Cl2] dimer with benzoyl azides. The novel compounds were characterized by spectroscopic and crystallographic methods. It was demonstrated that a p?-p? interaction between the bridging imido nitrogen atom and the carbonyl carbon atom results in unusually short N-C(O) bonds, which hampers the free rotation about this bond. The reaction was found to obey the Hammett equation

Önszerveződő fémorganikus vegyületek szintézise és szerkezeti jellemzése = Synthesis and structural characterization of self-assembled organometallic compounds

A SZTÉRIKUS HATÁS MEGNYILVÁNULÁSA PALLÁDIUMKOMPLEXEK ÖNSZERVEZŐDÉSÉBEN. Megfigyeltük, hogy 4,4?-bpy és különböző térigényű [Pd(NÇN)(NO3)2] komplexek reakciójában a kelátképző ligandum méretétől függően trimer vagy tetramer komplexek képződnek főtermékként. Megállapítottuk, hogy a legkisebb térigényű fémkomplexek (NÇN = etilén-diamin vagy homopiperazin) esetében is kimutatható trimer termék. Geometriai megfontolások alapján sztérikusan különböző koordinációs helyeket tartalmazó, új Ar-BIAN ligandumokat állítottunk elő. Kimutattuk, hogy nagy térigényű palládiumkomplexekkel való reakcióikban az elsődleges koordinációs helyet a terminális piridilcsoportok jelentik a sztérikusan gátolt kelátképző helyekkel szemben, ami a két koordinációs hely szigorúan konszekutív részvételében mutatkozik meg. Különböző térigényű palládiumkomplexek egyidejű jelenlétében a sztérikus hatás méret szerinti szelektív koordinációban nyilvánul meg. KATIONOK HATÁSA ÓNTARTALMÚ MAKROCIKLUSOK ÖNSZERVEZŐDÉSÉRE. A trimetilón(IV)-klorid reagálva a szupramolekuláris [Me3Sn(cupf)]4 tetramert eredményezi. Ezt a metatézist Na+-ionok jelenlétében megvalósítva, a képződött komplex dimetilón(IV) dimer, [Me2Sn(cupf)2]2. A tetramer metilcsoport vándorlással végbemenő diszmutációval alakul át dimerré és tetrametilónná. NMR vizsgálatokkal értelmeztük a tetramer dizmutációs átalakulását. Az organoón(IV) szupramolekulákra gyakorolt oldószerhatás nem szupramolekuláris izomer, hanem új szupramolekula kialakulását eredményezi. | STERIC EFFECTS IN THE SELF-ASSEMBLY OF Pd-COMPLEXES. We have found that the interaction of 4,4?-bpy with sterically different [Pd(NÇN)](NO3)2 complexes may result in either tetramers or trimers as major products. We have demonstrated that trimeric species are formed even with the sterically least congested tectons (NÇN = ethylenediamine or homopiperazine). Based on geometric considerations, we have prepared novel Ar-BIAN ligands with sterically different coordination sites. We have shown that the terminal pyridyl groups are preferred over the internal chelating nitrogen atoms in self-assembly with sterically demanding palladium complexes, which causes a strictly consecutive coordination of the metal complexes at the sterically different coordination sites. The steric effects manifest themselves in size-selective coordination when complexes of different bulkiness interact with the Ar-BIAN ligand. CATIONIC EFFECT IN THE SELF-ASSEMBLY OF TIN MACROCYCLES. The reaction of trimethyltin(IV)-chloride with cupferon results in a self-organized [Me3Sn(cupf)]4 tetramer. This metathesis carried out in the presence of Na+ ions provides dimethyltin(IV) dimer, [Me2Sn(cupf)2]2.The transformation of the tetramer involves a dismutation with methyl-migration. The mechanism of this transformation was analyzed by NMR methods. The solvent effects on the Sn(IV) supramolcules results in a new supramolecule rather than a supramolecular isomer

Increased resting-state EEG functional connectivity in benign childhood epilepsy with centro-temporal spikes

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Increased resting-state EEG functional connectivity in benign childhood epilepsy with centro-temporal spikes

AbstractPurposeTo explore intrahemispheric, cortico-cortical EEG functional connectivity (EEGfC) in benign childhood epilepsy with rolandic spikes (BECTS).Methods21-channel EEG was recorded in 17 non-medicated BECTS children and 19 healthy controls. 180s of spike- and artifact-free activity was selected for EEGfC analysis. Correlation of Low Resolution Electromagnetic Tomography- (LORETA-) defined current source density time series were computed between two cortical areas (region of interest, ROI). Analyses were based on broad-band EEGfC results. Groups were compared by statistical parametric network (SPN) method. Statistically significant differences between group EEGfC values were emphasized at p<0.05 corrected for multiple comparison by local false discovery rate (FDR).Results(1) Bilaterally increased beta EEGfC occurred in the BECTS group as compared to the controls. Greatest beta abnormality emerged between frontal and frontal, as well as frontal and temporal ROIs. (2) Locally increased EEGfC emerged in all frequency bands in the right parietal area.ConclusionsAreas of increased EEGfC topographically correspond to cortical areas that, based on relevant literature, are related to speech and attention deficit in BECTS children

A new xantphos-type ligand and its gold(I) complexes: Synthesis, structure, luminescence

A novel xantphos analog diphosphine ligand, 9,9-dimethyl-4,5-bis(diphenylphosphinomethyl)-9H-xanthene (X(CP)2), with methylene groups inserted between the xanthene skeleton and the two diphenylphosphine units, has been synthesized. A two-coordinate and a three-coordinate gold(I) complex of the ligand, [Au2Cl2(X(CP)2)] and [AuCl(X(CP)2)], have been prepared and studied by X-ray diffraction, NMR and optical spectroscopy. In the solid state, [AuCl(X(CP)2)] adopts a highly ordered structure with a planar xanthene skeleton that faces another plane composed of two phenyl rings and the AuCl moiety. The structure of [Au2Cl2(X(CP)2)] is much less regular, the two P–Au–Cl vectors point to the opposite sides of the folded xanthene backbone. The exchange-broadened resonances in the NMR spectra of [AuCl(X(CP)2))] indicate that this complex exists as a mixture of various chemical species and/or conformers in solution. In contrast, the NMR spectra of [Au2Cl2(X(CP)2)] exclude any medium-range exchange processes. Aurophilic interactions are absent in both X(CP)2 complexes. X(CP)2, as well as its two gold complexes, is phosphorescent in the solid state; the complexes emit at higher wavelengths and with longer lifetimes than the free ligand

Gene expression analysis of vascular pathophysiology related to anti-TNF treatment in rheumatoid arthritis

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A new heterotopic Ar-BIAN ligand with a pendant P donor site

Abstract The heterotopic ligand 1-[4-(4-diphenylphosphanylphenyl)phenylimino]-2-[3,5-bis(trifluoromethyl)phenylimino]acenaphthene, PN2, was prepared and characterized by NMR spectroscopic and MS methods. Depending on the size and the electronic properties of the metal reagent M, the two binding sites of the new ligand show selective coordination. At 1:1 molar ratio of PN2 and M, the sterically more demanding [Pd(dppe)]2+ and [Pd(dppp)]2+ cations coordinate only to the chelating nitrogen atoms while the less bulky [Pd(dppm)]2+ binds both to the imino and the phosphane donor groups. A 2:1:2 mixture of PN2, [Pd(dppm)(OTf)2] and [Pd(dppe)(OTf)2] results in the formation of a complex in which the [Pd(dppm)]2+ unit selectively coordinates to the terminal P atoms while the more voluminous dppe counterpart resides at the imino nitrogens. On the contrary, the [Pd(dppm)]2+ complex selectively binds to the chelating nitrogen atoms if the Ph2P group is ligated to Au+ center. In the interaction of [Au(PN2)2]PF6 with Ag(OTf), the silver ions do not replace Au+ in the P–Au bonds but occupy the chelating position