Metal complexes catalyzed processes as the basis for the synthesis of new alkynylsubstituted organogermanium and organogermasilicon compounds

Wydział ChemiiGłównym celem naukowym pracy doktorskiej było opracowanie nowych, skutecznych metod syntezy nowych alkinylopodstawionych związków germano- i germanokrzemoorganicznych w oparciu o reakcje katalityczne. W pracy wykorzystano dotychczasowe dokonania w dziedzinie katalizy z udziałem kompleksów metali przejściowych (rutenu i irydu), które charakteryzują się wysoką wydajnością i selektywnością. Opracowano metodę funkcjonalizacji etynylopodstawionych silseskwioksanów z winylogermananami oraz warunki reakcji germylującego sprzęgania 1,4-bis(dimetylowinylogermylo)benzenu z alkinami. Obie grupy reakcji prowadzone były z udziałem hydrydowego kompleksu rutenu(II). Zaproponowano także nową reakcję sprzęgania alkinów z halogenogermananami (jodkami i chlorkami) w obecności kompleksu irydu(I), będącą efektywną metodą syntezy nienasyconych produktów zarówno mono-, jak i dwupodstawionych. Otrzymane produkty zostały wyizolowane i w pełni scharakteryzowane przy użyciu metod spektroskopowych magnetycznego rezonansu jądrowego i GCMS lub poddane analizie GCMS w postaci izolowanej mieszaniny produktów. Ponadto przeprowadzono szereg reakcji stechiometrycznych służących wyjaśnieniu mechanizmu reakcji germylującego sprzęgania jodogermananów z terminalnymi alkinami. Wyniki badań eksperymentalnych poparto także serią obliczeń z wykorzystaniem kwantowo-chemicznej metody Teorii Funkcjonału Gęstości (DFT).The main scientific aim of this doctoral thesis was to propose new and effective methods for the syntheses of new alkynylsubstituted organogermanes in catalytic reactions. In this thesis, a new catalytic route to the synthesis of alkynylsubstituted organogermanium and organogermasilicon compounds is reported. The principal reaction taken into consideration in the study was germylative coupling of ethynylsubstituted silsesquioxanes with vinyl derivatives of germanium and reaction between 1,4-bis(dimethylvinylgermyl)benzene and terminal alkynes (in the presence of ruthenium(II) complexes). Another reaction studied was that of terminal alkynes with halogermanes, proceeding in the presence of an iridium(I) complex and amine as a hydrogen iodide/chloride acceptor. Moreover, a new and universal (considering halogermane compounds) catalytic method for the synthesis of unsaturated organogermanium compounds was proposed. Most of the obtained products are new compounds, they were isolated and characterized by spectroscopic methods (GCMS and NMR). I extended my research to the studies of mechanism of germylative coupling of terminal alkynes and halogermanes. The DFT calculations were also performed to confirm the mechanistic pathway

Preparation of Tri(alkenyl)functional Open-Cage Silsesquioxanes as Specific Polymer Modifiers

The scientific reports on polyhedral oligomeric silsesquioxanes are mostly focused on the formation of completely condensed T8 cubic type structures and recently so-called double-decker derivatives. Herein, we report on efficient synthetic routes leading to trifunctionalized, open-cage silsesquioxanes with alkenyl groups of varying chain lengths from -vinyl to -dec-9-enyl and two types of inert groups (iBu, Ph) at the silsesquioxane core. The presented methodology was focused on hydrolytic condensation reaction and it enabled obtaining titled compounds with high yields and purity. A parallel synthetic methodology that was based on the hydrosilylation reaction was also studied. Additionally, a thorough characterization of the obtained compounds was performed, also in terms of their thermal stability, melting and crystallization temperatures (TGA and DSC) in order to show the changes in the abovementioned parameters dependent on the type of reactive as well as inert groups at Si-O-Si core. The presence of unsaturated alkenyl groups has a profound impact on the application potential of these systems, i.e., as modifiers or comonomers for copolymerization reaction

Slick Synthetic Approach to Various Fluoroalkyl Silsesquioxanes—Assessment of their Dielectric Properties

We present a smart and efficient methodology for the synthesis of a variety of fluorinated silsesquioxanes (SQs) with diverse Si-O-Si core architecture. The protocol is based on an easy-to-handle and selective hydrosilylation reaction. An investigation on the placement of the reactive Si-HC=CH2 vs. Si-H in the silsesquioxane, as well as silane vs. olefin structure, respectively, on the progress and selectivity of the hydrosilylation process, was studied. Two alternative synthetic pathways for obtaining a variety of fluorine-functionalized silsesquioxanes were developed. As a result, a series of mono- and octa- T8 SQs, tri- ‘open-cage’ T7 SQs, in addition to di- and tetrafunctionalized double-decker silsesquioxane (DDSQ) derivatives, were obtained selectively with high yields. All products were characterized by spectroscopic (NMR, FTIR) techniques. Selected samples were subjected to the measurements revealing their dielectric permittivity in a wide range of temperatures (from −100 °C to 100 °C) and electric field frequencies (100–106 Hz)

Double-Decker Silsesquioxanes Self-Assembled in 1D Coordination Polymeric Nanofibers with Emitting Properties

[Image: see text] The urgent needs for photoactive materials in industry drive fast evolution of synthetic procedures in many branches of chemistry, including the chemistry of silsesquioxanes. Here, we disclose an effective protocol for the synthesis of novel double-decker silsesquioxanes decorated with two (styrylethynylphenyl)terpyridine moieties (DDSQ_Ta-b). The synthesis strategy involves a series of silylative and Sonogashira coupling reactions and is reported for the first time. DDSQ_Ta-b were employed as nanocage ligands to promote self-assembly in the presence of transition metals (TM), i.e., Zn(2+), Fe(2+), and Eu(3+) ions, to form one-dimensional (1D) coordination polymeric nanofibers. Additionally, ultraviolet-promoted and reversible E–Z isomerization of the C=C bond within the ligand structures may be exploited to tune their emission properties. These findings render such complexes promising candidates for applications in materials chemistry. This is the first example of 1D coordination polymers bearing DDSQ-based nodes with TM ions