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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Rotationsstruktur- und Starkeffektuntersuchungen an ausgewählten aromatischen Molekülen im Überschalldüsenstrahl mittels hochauflösender UV-Laserspektroskopie

Okruss, Michael. January 2005 (has links) (PDF)
Berlin, Techn. Univ., Diss., 2005. / Computerdatei im Fernzugriff.
2

Vytvoření a analýza in-house databáze derivátů pyrazinu s potenciálně antimikrobními účinky / Creation and analysis of in-house database of pyrazine derivatives with potential antimicrobial activity

Kebakuile, Legae Gomolemo Boemo January 2018 (has links)
In the early phases of drug design and development, scientists must overcome many challenges involved in identifying potential drug-like or lead-like compounds. This has led to the need of creating large sets of chemical data which will aid in improving the identification of pharmacophores and active compounds. Various scientific fields especially pharmacology, medicinal chemistry and biochemistry have begun to employ the use of computer sciences to aid in the screening for potential leads with more specificity with regards to drug-like compounds' or substances' bioactivity. The emphasis of this project was to create a database containing a collection of pyrazine compounds synthesized overtime in the Faculty of Pharmacy (Charles University, Hradec Kralove) with the aim of having anti-mycobacterium (and possible antibacterial and antifungal) activity, and further utilize this database to predict certain pharmacokinetic and bioavailability properties. This project seeks to demonstrate how certain molecular descriptors can be used as reliable chemoinformation to determine the likeliness or possibility of developing a lead-like or drug-like compound by utilizing computer software. An in-house database of 623 compounds saved in SMILES format was created and used in demonstrating quantitative...
3

Vytvoření a analýza in-house databáze derivátů pyrazinu s potenciálně antimikrobními účinky / Creation and analysis of in-house database of pyrazine derivatives with potential antimicrobial activity

Kebakuile, Legae Gomolemo Boemo January 2018 (has links)
In the early phases of drug design and development, scientists must overcome many challenges involved in identifying potential drug-like or lead-like compounds. This has led to the need of creating large sets of chemical data which will aid in improving the identification of pharmacophores and active compounds. Various scientific fields especially pharmacology, medicinal chemistry and biochemistry have begun to employ the use of computer sciences to aid in the screening for potential leads with more specificity with regards to drug-like compounds' or substances' bioactivity. The emphasis of this project was to create a database containing a collection of pyrazine compounds synthesized overtime in the Faculty of Pharmacy (Charles University, Hradec Kralove) with the aim of having anti-mycobacterium (and possible antibacterial and antifungal) activity, and further utilize this database to predict certain pharmacokinetic and bioavailability properties. This project seeks to demonstrate how certain molecular descriptors can be used as reliable chemoinformation to determine the likeliness or possibility of developing a lead-like or drug-like compound by utilizing computer software. An in-house database of 623 compounds saved in SMILES format was created and used in demonstrating quantitative...
4

Rotationsstruktur- und Starkeffektuntersuchungen an ausgewählten aromatischen Molekülen im Überschalldüsenstrahl mittels hochauflösender UV-Laserspektroskopie

Okruss, Michael. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2005--Berlin.
5

Návrh, syntéza a biologické hodnocení 2,3-disubstituovaných pyrazinů / Design, synthesis and biological evaluation of 2,3-disubstituted pyrazines

Kerda, Marek January 2020 (has links)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Supervisor: Assoc. Prof. PharmD. Jan Zitko, PhD. Author: Marek Kerda Title of diploma thesis: Design, synthesis and biological evaluation of 2,3-disubstituted pyrazines This thesis deals with problem of tuberculosis. In a theoretical part are summarized information and knowledge about tuberculosis, nowadays epidemiology and drugs used in current treatment. There are also described drugs in the different stage of clinical trials and could be used for treatment of tuberculosis in the future. Searched information were used from accessible learning materials and in articles in online databases as Web of Science and PubMed. There are also summarized basic methods of computer design of new drugs. In practical part of this thesis was focus on novel inhibitor of prolyl-tRNA synthetase, which is based on structure of pyrazinamide. There was prepared in silico virtual library of pyrazine-based new potential ligands. Related docking to the structure of human prolyl t-RNA (pdb: 5VAD) and the bacterial version of this enzyme (pdb: 2J3M) and evaluation was performed in Molecular Operating Environment (Chemical Computing Group, Canada). From the results were predicted some of the relations between structure and activity. Virtual library of the...
6

Deriváty 5-alkylpyrazin-2-karboxylové kyseliny jako potenciální antiinfektiva / Derivatives of 5-alkylpyrazine-2-carboxylic acid as potential anti-infectives

Halířová, Martina January 2017 (has links)
DERIVATIVES OF 5-ALKYLPYRAZINE-2-CARBOXYLIC ACID AS POTENTIAL ANTI-INFECTIVES HALÍŘOVÁ MARTINA Department of Pharmaceutical Chemistry and Drug Analysis, Faculty of Pharmacy in Hradec Králové, Charles University, Czech Republic In our previous study, we have demonstrated that 5-alkylamino-N- phenylpyrazine-2-carboxamides with longer alkyl chain (C5-C8) exerted micromolar growth inhibition activity against M. tuberculosis H37Rv. We speculated that the long alkylamino chain could facilitate the penetration of lipophilic mycobacterial cell envelope. To test this hypothesis, we performed the amino to methylene isosteric exchange and designed a series of 5-alkyl-N-phenylpyrazine-2-carboxamides. 5- Alkylpyrazine-2-carboxylic acids (5-Ak-POA) were prepared by homolytic alkylation of commercially available pyrazine-2-carbonitrile by respective alkanoic acid, followed by hydrolysis of the carbonitrile group. Final derivatives were prepared by CDI mediated coupling of 5-Ak-POA with corresponding aniline at RT. Final compounds were described by melting point, elementary analysis, IR spectroscopy and 1 H, 13 C NMR. Then they were tested in vitro for antimycobacterial activity against M. tuberculosis H37Rv and several non-tuberculous mycobacterial strains. Several compounds exerted MIC of 3.13-6.25 µg mL-1 ....
7

Syntéza a antiinfekční hodnocení substituovaných N-(pyrazin-2-yl)benzensulfonamidů / Synthesis and antiinfective evaluation of substituted N-(pyrazin-2-yl)benzenesulfonamides

Paredes De La Red, Cristina January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Author: Cristina Paredes de la Red Supervisor: prof. PharmDr. Martin Doležal, Ph.D. Title of diploma thesis: Synthesis and antiinfective evaluation of substituted N-(pyrazine-2- yl)benzenesulfonamide Tuberculosis (TB) is among the ten leading causes of death, especially in developing countries. Even though it is an old disease with established treatment regimen, there has been an increased resistance to anti-TB drugs 1 . The anti-tubercular pyrazinamide has caught the attention of researchers as the different theories for its mechanism of action have made it an interesting entity for further investigation. Here we will discuss N-(pyrazine-2-yl)benzenesulfonamides (General structure is presented in the Figure below) as a new derivatization approach based on synergism methodology between pyrazinamide and sulfonamides. Sulfonamides exert their antimicrobial effect by competitive inhibition of folic acid synthesis and subsequent inhibition of bacterial growth and reproduction 18 . I have contributed to the synthesis and purification of 8 compounds in a series of total 22 N- pyrazinylsulfonamides. Two of the prepared compounds showed activity against Mycobacterium kansasii [2a (MIC...
8

Simulation of nonadiabatic dynamics and time-resolved photoelectron spectra in the frame of time-tependent density functional theory

Werner, Ute 25 July 2011 (has links)
Ziel dieser Arbeit war die Entwicklung einer allgemein anwendbaren Methode für die Simulation von ultraschnellen Prozessen und experimentellen Observablen. Hierfür wurden die Berechnung der elektronischen Struktur mit der zeitabhängigen Dichtefunktionaltheorie (TDDFT) und das Tully-Surface-Hopping-Verfahren für die nichtadiabatische Kerndynamik auf der Basis klassischer Trajektorien miteinander kombiniert. Insbesondere wurde eine Beschreibung der nichtadiabatischen Kopplungen für TDDFT entwickelt. Diese Methode wurde für die Simulation noch komplexerer Systeme durch die Tight-Binding-Näherung für TDDFT erweitert. Da die zeitaufgelöste Photoelektronenspektroskopie (TRPES) ein exzellentes experimentelles Verfahren für die Echtzeitbeobachtung von ultraschnellen Prozessen darstellt, wurde eine TDDFT-basierte Methode für die Simulation von TRPES entwickelt. Der Methode liegt die Idee zu Grunde, das System aus Kation und Photoelektron näherungsweise durch angeregte Zustände des neutralen Moleküls oberhalb der Ionisierungsgrenze zu beschreiben. Um diese Zustände mit TDDFT berechnen zu können wurde eine Beschreibung der Übergangsdipolmomente zwischen angeregten TDDFT-Zuständen entwickelt. Des Weiteren wurden Simulationen im Rahmen des Stieltjes-Imaging-Verfahrens, das eine Möglichkeit der Rekonstruktion des Photoelektronenspektrums aus den spektralen Momenten bietet, durchgeführt. Diese spektralen Momente wurden aus den diskreten TDDFT-Zuständen berechnet. Die breite Anwendbarkeit der entwickelten theoretischen Methoden für die Simulation von komplexen Systemen wurde an der Photoisomerisierung in Benzylidenanilin sowie der ultraschnellen Photodynamik in Furan, Pyrazin und mikrosolvatisiertem Adenin illustriert. Die dargestellten Beispiele demonstrieren, dass die nichtadiabatische Dynamik im Rahmen von TDDFT bzw. TDDFTB sehr gut für die Untersuchung und Interpretation der ultraschnellen photoinduzierten Prozesse in komplexen Molekülen geeignet ist. / The goal of this thesis was the development of a generally applicable theoretical framework for the simulation of ultrafast processes and experimental observables in complex molecular systems. For this purpose, a combination of the time-dependent density functional theory (TDDFT) for the description of the electronic structure with the Tully''s surface hopping procedure for the treatment of nonadiabatic nuclear dynamics based on classical trajectories was employed. In particular, a new approach for the calculation of nonadiabatic couplings within TDDFT was devised. The method was advanced for the description of more complex systems such as chromophores in a solvation shell by employing the tight binding approximation to TDDFT. Since the time-resolved photoelectron spectroscopy (TRPES) represents a powerful experimental technique for real-time observation of ultrafast processes, a TDDFT based approach for the simulation of TRPES was developed. The basic idea is the approximate representation of the combined system of cation and photoelectron by excited states of the neutral species above the ionization threshold. In order to calculate these states with TDDFT, a formulation of the transition dipole moments between excited states within TDDFT was devised. Moreover, simulations employing the Stieltjes imaging (SI) procedure were carried out providing the possibility to reconstruct photoelectron spectra from spectral moments. In this work, the spectral moments were calculated from discrete TDDFT states. The scope of the developed theoretical methods was illustrated on the photoisomerization in benzylideneaniline as well as on the ultrafast photodynamics in furan, pyrazine, and microsolvated adenine. The examples demonstrate that the nonadiabatic dynamics simulations based on TDDFT and TDDFTB are particularly suitable for the investigation and interpretation of ultrafast photoinduced processes in complex molecules.
9

Rigid-Rod Structured Homobimetallic Complexes

Alansawi, Deeb 13 April 2005 (has links) (PDF)
The synthesis and reaction chemistry of trans-(PPh3)2Pd(C6H4-4-I)(X) (X = I, OTf) is discussed. Treatment of trans- (PPh3)2Pd(C6H4- 4-I)(OTf) with bidentate Lewis-bases (N)N), such as pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2 or C6H4-1,4-CN produces, depending on N)N, mono- or bimetallic species of type [trans- (PPh3)2Pd(C6H4-4-I)(N)N)]+ or [trans-(Ph3P)2(C6H4- 4-I)Pd N)N Pd- (PPh3)2(C6H4-4-I)]2+. These new complexes rearrange in the solution to give [trans-[(Ph3P)2Pd(C6H4-4-PPh3)(N)N)]2+ (N)N = C4H4N2, C5H4N-4-CN, NaC-4-C5H4N) and [trans-[(Ph3P)2(C6H4-4-PPh3)- Pd N)N Pd(PPh3)2(C6H4-4-PPh3)]4+ (N)N = C6H4-1,4-(CN)2, (C6H4-4- CN)2) along with {[(Ph3P)2(Ph3P-4-C6H4)Pd -(µ-I)]2}2+. The mechanism is elucidated. The latter species are rigid-rod structured. The preparation of mono- and homo-bimetallic palladium complexes of type [(Me(O)CS-4-C6H4)(PPh3)2Pd -(N)N)]+ and {[(Me- (O)CS-4-C6H4)(PPh3)2Pd]2(N)N)} 2+ (N)N = pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2, C6H4-1,4-CN) is reported. The formation of the mono- or bimetallic species depends on the size of the Lewis bases N)N. The use of these molecules as molecular wire is discussed. The synthesis of homo-bimetallic palladium molecular wire complexes of type {[(Me(O)CS-4-C6H4-C6H4)(PPh3)2Pd]2(N)N)}2+ is described. The structural aspects of these complexes in the solid-state by single X-ray crystallography is discussed. The synthesis, characterization and electrochemical properties of a new series of homo-bimetallic palladium and platinum complexes of type [Me(O)CS-NCN-M]2(N)N) (NCN = [C6H2(CH2NMe2)2- 2,6)]-) is described. The effect of the para-substituent of the functionalized thio-acetyl NCN ligand on the electrochemical properties of the incorporated platinum center is discussed. The selective synthesis of acetylene and acyl-thiol endcapped heterobimetallic organometallic pi-tweezer of type {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-R ([Ti] = (eta5-C5H4SiMe3)2Ti; R = SiMe3; R = CCH,R = SC(O)Me) succeeds by the reaction of {[Ti](CCR)2}CuCH3 with equimolar amounts of Me(O)CSC6H4-4-CCH or the dithiol C6H4-1,4-(SC(O)Me)2. Binuclear (µ-RSe)(µ sigma,pi CCPh)Fe2(CO)6 can be prepared by treatment of RSe-CCPh (R = Et, nBu, Ph, 2,4,6-Me3C6H2) with Fe2(CO)9 in tetrahydrofuran at room temperature. In solution two isomers exist, depending on the position of the lone-pair of electrons present at selenium (axial or equatorial, respectively). Nucleophilic addition of P(OiC3H7)3 to (µ-RSe)- (µ -sigma,pi CCPh)Fe2(CO)6 affords vinylidene- and dimetallacylobutene- bridged complexes Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)(µ-eta1C=C(Ph)- (P(OiC3H7)3) and [Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ -eta1:eta1(Ph)C=C- {P(OiC3H7)3). The isolated complexes were characterized by multinuclear NMR (1H, 13C{1H}, and 31P{1H}, elemental analysis, FT-IR, and single x-ray crystallography. / Ein Ziel der Arbeit war die Synthese von trans-(PPh3)2Pd(C6H4-4-I)(X) (X = I, OTf) und Untersuchungen zu dessen Reaktionsverhalten. Die Zugabe von zweizähnigen Lewis-Basen (N)N), wie z.B. pz, pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2 oder C6H4-1,4-CN ergibt, abhängig von (N)N), mono- oder bimetallische Spezies vom Typ [trans-(PPh3)2Pd(C6H4-4-I)(N)N)]+ oder [trans-(Ph3P)2(C6H4-4-I)Pd N)N Pd-(PPh3)2(C6H4-4-I)]2+. Diese in Lösung instabilen Komplexe reagieren weiter zu [trans-[(Ph3P)2Pd(C6H4-4-PPh3)(N)N)]2+ (N)N = C4H4N2, C5H4N- 4-CN, NC-4-C5H4N) oder [trans-[(Ph3P)2(C6H4-4-PPh3)Pd N)N Pd(PPh3)2-(C6H4-4- PPh3)]4+ (N)N = C6H4-1,4-(CN)2, (C6H4-4-CN)2) zusammen mit {[(Ph3P)2(Ph3P-4- C6H4)Pd(µ-I)]2}2+. Der Mechanismus dieser Reaktionsfolge wurde aufgeklärt. Diese Komplexe besitzen eine starre, lineare Struktur, welche unter anderem mittels Röntgeneinkristallstrukturanalyse ermittelt wurde. Weiterhin wird über die Darstellung von mono- und homobimetallischen Palladium-Komplexen vom Typ [(Me(O)CS-4-C6H4)(PPh3)2Pd(N)N)]+ und {[(Me- (O)CS-4-C6H4)(PPh3)2Pd]2(N)N)}2+ (N)N = pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2, C6H4-1,4-CN) berichtet. Die Bildung von homo- oder bimetallischen Spezies hängt von der Größe der Lewis-Base N)N ab. Die Anwendung dieser Moleküle als molekulare Drähte wird, zusammen mit der Festkörperstruktur zweier dieser Komplexe, diskutiert. Die Synthese von homobimetallischen Pd Komplexen vom Typ {[(Me(O)CS-4- C6H4-C6H4)(PPh3)2Pd]2(N)N)}2+ (molekulare Drähte) wird beschrieben. Die strukturellen Aspekte dieser Komplexe im festen Zustand werden diskutiert Die Synthese, Charakterisierung und elektrochemischen Eigenschaften einer neuen Serie von homobimetallischen Pd und Pt Komplexen vom Typ [Me(O)CSNCN- M]2(N)N) (NCN = [C6H2(CH2NMe2)2-2,6)]-) wird beschrieben. Der Effekt des para-Substituenten der funktionalisierten Thioacetyl-NCN Liganden auf die elektrochemischen Eigenschaften des komplexierten Pt wird diskutiert. Die selektive Synthese von Alkinyl- und Thioacetyl-funkionalisierten heterobimetallischen metallorganischen pi-Pinzetten-Komplexen vom Typ {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-CCH und {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-SC(O)Me ([Ti] = (eta5-C5H4SiMe3)2Ti; R = SiMe3, R = tBu) erfolgt durch die Reaktion von {[Ti](CCR)2}CuCH3 (R = SiMe3, R = tBu) mit äquimolaren Mengen an Me(O)CS-1- C6H4-4-CCH oder des Dithiols C6H4-1,4-(SC(O)Me)2. Im Vorgang dieser Reaktion wird Aceton gebildet. Zweikernige (µ-RSe)(µ sigma,pi CCPh)Fe2(CO)6 Komplexe können durch die Umsetzung von RSe-CCPh (R = Et, nBu, Ph, 2,4,6-Me3C6H2) mit Fe2(CO)9 in Tetrahydrofuran bei 20 °C dargestellt werden. In Lösung liegen, in Abhängigkeit von der Position des freien Elektronenpaares am Selen (axial oder äquatorial), zwei Isomere vor. Addition von P(OiC3H7)3 zu (µ-RSe)(µ sigma,pi CCPh)Fe2-(CO)6 ergibt Vinyliden- Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ-eta1 C=C-(Ph)(P(OiC3H7)3) und Dimetallacyclobuten- verbrückte Komplexe der Art [Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ-eta1:eta1- (Ph)C=C{P(OiC3H7)3). Die isolierten Komplexe wurden durch die Elementaranalyse, spektroskopisch (1H, 13C{1H}, 31P{1H} NMR; IR) und die Röntgeneinkristallstrukturanalyse charakterisiert.
10

Rigid-Rod Structured Homobimetallic Complexes

Alansawi, Deeb 21 March 2005 (has links)
The synthesis and reaction chemistry of trans-(PPh3)2Pd(C6H4-4-I)(X) (X = I, OTf) is discussed. Treatment of trans- (PPh3)2Pd(C6H4- 4-I)(OTf) with bidentate Lewis-bases (N)N), such as pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2 or C6H4-1,4-CN produces, depending on N)N, mono- or bimetallic species of type [trans- (PPh3)2Pd(C6H4-4-I)(N)N)]+ or [trans-(Ph3P)2(C6H4- 4-I)Pd N)N Pd- (PPh3)2(C6H4-4-I)]2+. These new complexes rearrange in the solution to give [trans-[(Ph3P)2Pd(C6H4-4-PPh3)(N)N)]2+ (N)N = C4H4N2, C5H4N-4-CN, NaC-4-C5H4N) and [trans-[(Ph3P)2(C6H4-4-PPh3)- Pd N)N Pd(PPh3)2(C6H4-4-PPh3)]4+ (N)N = C6H4-1,4-(CN)2, (C6H4-4- CN)2) along with {[(Ph3P)2(Ph3P-4-C6H4)Pd -(µ-I)]2}2+. The mechanism is elucidated. The latter species are rigid-rod structured. The preparation of mono- and homo-bimetallic palladium complexes of type [(Me(O)CS-4-C6H4)(PPh3)2Pd -(N)N)]+ and {[(Me- (O)CS-4-C6H4)(PPh3)2Pd]2(N)N)} 2+ (N)N = pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2, C6H4-1,4-CN) is reported. The formation of the mono- or bimetallic species depends on the size of the Lewis bases N)N. The use of these molecules as molecular wire is discussed. The synthesis of homo-bimetallic palladium molecular wire complexes of type {[(Me(O)CS-4-C6H4-C6H4)(PPh3)2Pd]2(N)N)}2+ is described. The structural aspects of these complexes in the solid-state by single X-ray crystallography is discussed. The synthesis, characterization and electrochemical properties of a new series of homo-bimetallic palladium and platinum complexes of type [Me(O)CS-NCN-M]2(N)N) (NCN = [C6H2(CH2NMe2)2- 2,6)]-) is described. The effect of the para-substituent of the functionalized thio-acetyl NCN ligand on the electrochemical properties of the incorporated platinum center is discussed. The selective synthesis of acetylene and acyl-thiol endcapped heterobimetallic organometallic pi-tweezer of type {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-R ([Ti] = (eta5-C5H4SiMe3)2Ti; R = SiMe3; R = CCH,R = SC(O)Me) succeeds by the reaction of {[Ti](CCR)2}CuCH3 with equimolar amounts of Me(O)CSC6H4-4-CCH or the dithiol C6H4-1,4-(SC(O)Me)2. Binuclear (µ-RSe)(µ sigma,pi CCPh)Fe2(CO)6 can be prepared by treatment of RSe-CCPh (R = Et, nBu, Ph, 2,4,6-Me3C6H2) with Fe2(CO)9 in tetrahydrofuran at room temperature. In solution two isomers exist, depending on the position of the lone-pair of electrons present at selenium (axial or equatorial, respectively). Nucleophilic addition of P(OiC3H7)3 to (µ-RSe)- (µ -sigma,pi CCPh)Fe2(CO)6 affords vinylidene- and dimetallacylobutene- bridged complexes Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)(µ-eta1C=C(Ph)- (P(OiC3H7)3) and [Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ -eta1:eta1(Ph)C=C- {P(OiC3H7)3). The isolated complexes were characterized by multinuclear NMR (1H, 13C{1H}, and 31P{1H}, elemental analysis, FT-IR, and single x-ray crystallography. / Ein Ziel der Arbeit war die Synthese von trans-(PPh3)2Pd(C6H4-4-I)(X) (X = I, OTf) und Untersuchungen zu dessen Reaktionsverhalten. Die Zugabe von zweizähnigen Lewis-Basen (N)N), wie z.B. pz, pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2 oder C6H4-1,4-CN ergibt, abhängig von (N)N), mono- oder bimetallische Spezies vom Typ [trans-(PPh3)2Pd(C6H4-4-I)(N)N)]+ oder [trans-(Ph3P)2(C6H4-4-I)Pd N)N Pd-(PPh3)2(C6H4-4-I)]2+. Diese in Lösung instabilen Komplexe reagieren weiter zu [trans-[(Ph3P)2Pd(C6H4-4-PPh3)(N)N)]2+ (N)N = C4H4N2, C5H4N- 4-CN, NC-4-C5H4N) oder [trans-[(Ph3P)2(C6H4-4-PPh3)Pd N)N Pd(PPh3)2-(C6H4-4- PPh3)]4+ (N)N = C6H4-1,4-(CN)2, (C6H4-4-CN)2) zusammen mit {[(Ph3P)2(Ph3P-4- C6H4)Pd(µ-I)]2}2+. Der Mechanismus dieser Reaktionsfolge wurde aufgeklärt. Diese Komplexe besitzen eine starre, lineare Struktur, welche unter anderem mittels Röntgeneinkristallstrukturanalyse ermittelt wurde. Weiterhin wird über die Darstellung von mono- und homobimetallischen Palladium-Komplexen vom Typ [(Me(O)CS-4-C6H4)(PPh3)2Pd(N)N)]+ und {[(Me- (O)CS-4-C6H4)(PPh3)2Pd]2(N)N)}2+ (N)N = pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2, C6H4-1,4-CN) berichtet. Die Bildung von homo- oder bimetallischen Spezies hängt von der Größe der Lewis-Base N)N ab. Die Anwendung dieser Moleküle als molekulare Drähte wird, zusammen mit der Festkörperstruktur zweier dieser Komplexe, diskutiert. Die Synthese von homobimetallischen Pd Komplexen vom Typ {[(Me(O)CS-4- C6H4-C6H4)(PPh3)2Pd]2(N)N)}2+ (molekulare Drähte) wird beschrieben. Die strukturellen Aspekte dieser Komplexe im festen Zustand werden diskutiert Die Synthese, Charakterisierung und elektrochemischen Eigenschaften einer neuen Serie von homobimetallischen Pd und Pt Komplexen vom Typ [Me(O)CSNCN- M]2(N)N) (NCN = [C6H2(CH2NMe2)2-2,6)]-) wird beschrieben. Der Effekt des para-Substituenten der funktionalisierten Thioacetyl-NCN Liganden auf die elektrochemischen Eigenschaften des komplexierten Pt wird diskutiert. Die selektive Synthese von Alkinyl- und Thioacetyl-funkionalisierten heterobimetallischen metallorganischen pi-Pinzetten-Komplexen vom Typ {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-CCH und {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-SC(O)Me ([Ti] = (eta5-C5H4SiMe3)2Ti; R = SiMe3, R = tBu) erfolgt durch die Reaktion von {[Ti](CCR)2}CuCH3 (R = SiMe3, R = tBu) mit äquimolaren Mengen an Me(O)CS-1- C6H4-4-CCH oder des Dithiols C6H4-1,4-(SC(O)Me)2. Im Vorgang dieser Reaktion wird Aceton gebildet. Zweikernige (µ-RSe)(µ sigma,pi CCPh)Fe2(CO)6 Komplexe können durch die Umsetzung von RSe-CCPh (R = Et, nBu, Ph, 2,4,6-Me3C6H2) mit Fe2(CO)9 in Tetrahydrofuran bei 20 °C dargestellt werden. In Lösung liegen, in Abhängigkeit von der Position des freien Elektronenpaares am Selen (axial oder äquatorial), zwei Isomere vor. Addition von P(OiC3H7)3 zu (µ-RSe)(µ sigma,pi CCPh)Fe2-(CO)6 ergibt Vinyliden- Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ-eta1 C=C-(Ph)(P(OiC3H7)3) und Dimetallacyclobuten- verbrückte Komplexe der Art [Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ-eta1:eta1- (Ph)C=C{P(OiC3H7)3). Die isolierten Komplexe wurden durch die Elementaranalyse, spektroskopisch (1H, 13C{1H}, 31P{1H} NMR; IR) und die Röntgeneinkristallstrukturanalyse charakterisiert.

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