Synthese und Eigenschaften von Organozinnselenid- und Organosiliciumsulfid-Clustern

Table of Contents: The topic of this dissertation is the synthesis and reactivity of organotin selenide and organisilicon sulfide clusters. In the first part of this dissertation, the reactivity of organo-functionalized organotin selenide clusters with the general formula [(RfSn)xSey] (Rf = substituent with functional group; x, y ∈ N ) toward bifunctional compounds and toward [CuCl(PPh3)3] was investigated. The reaction of the doubledecker-type cluster [(R2Sn)4Se6] (R2 = CMe2CH2CMeNNH2) with o-phthalaldehyde yielded a doubledecker-type cluster whose substituents are connected intramolecularly in a crosswise manner. When reacting [(R1Sn)3Se4Cl] (R1 = CMe2CH2CMeO) with bifunctional compounds with longer chains, namely adipinic acid hydrazide or 1,1’-(1,5-naphthalenediyl)bishydrazine, bigger rugby ball-type capsule molecules with the general formula [(µ–R)3(Sn3Se4)2]2+ were obtained as their salts with [SnCl3]– or Cl– counterions. These cationic clusters contain solvent molecules and/or counter ions in their solid state. Mass spectrometric measurements showed that these capsules stay intact upon release of the solvent molecules and even under ESI-MS conditions it was possible to detect molecules with encapsulated anions. Furthermore, reactions of the doubledecker-type cluster [(R1Sn)4Se6] with (SiMe3)2Se and hydrazine hydrate or phenylhydrazine yielded the correspondingly substituted bisdefect heterocubane-type clusters [R4Sn6Se10] (R = R2, CMe2CH2CMeNNPhH). Although all of these structural motifs were already known for organotin sulfide clusters, they could be obtained for organotin selenide clusters for the first time in this work. The comparison of the inner volumes of the rugby ball-type molecules with each other and with that of the 1,1’-(1,5-naphthalenediyl)bishydrazine-based tinsulfide cluster showed that these are primarily dependent on the present substituents and the switch from sulfur to selenium as the chalcogenide barely affects the inner volume. 16 hours after the start of the reaction of [(R1Sn)4Se6] with [Cu(PPh3)3Cl], a bright orange powder was isolated whose exact composition is yet unknown. Depending on the reaction time, the addition of hydrazine hydrate to a suspension of this powder led to the formation of the ternary clusters [(Cu3Sn){(R2Sn)2Se4}2{(R2Sn2)Se3}]⋅1.87CH2Cl2⋅2solv (solv = CH2Cl2 and/or C6H14) (reaction time: 16 h) and [(N2H4)(Cu4Sn){(R2Sn)2Se4}3] (instant work-up after addition of hydrazine hydrate). Both clusters are based on a { CuxSn} core (x = 3, 4), which is mainly surrounded by {(RSn)2Se4} moieties. The latter are a common structural motif in ternary organotin coinage metal chalcogenide clusters. The comparison with the synthesis of the already known organo-functionalized Cu/Sn/Se clusters suggests a complex equilibrium in the respective reaction solutions, as even small changes to the reaction conditions lead to a variety of different clusters. In the last part of this dissertation, new adamantane-type organosilicon sulfide clusters with the general formula [(RSi)4S6] (R = 1-naphthyl (Np), 4-vinylphenyl (Sty)) were synthesized. Photophysical measurements were conducted in the Chatterjee group and showed second harmonic generation (SHG) for the crystalline [(NpSi)4S6], whereas no definite proof for white light generation (WLG) of [(StySi)4S6] exists yet, due to its lower stability. Quantumchemical calculations by the Mollenhauer group found an explanation for the organosilicon sulfide clusters’ higher tendency to crystallize as compared to the analog organotin sulfide clusters: In the organotin sulfide clusters, the relatively isotropic cluster core-cluster core interactions have a significantly higher influence than the directional interactions with substituent-contribution. In the organosilicon sulfide clusters, this difference is much lower which leads to a higher degree of intermolecular order and ultimately to crystallization. First experiments on the reactivity of adamantane-type organo-silicon sulfide clusters showed a similar behavior to organotin sulfide clusters. The reactions of [(PhSi)4S6] or [(NpSi)4S6] with [AuCl(PPh3)] resulted in the partial decomposition of the clusters and the subsequent formation of organosilicon gold-sulfide complexes with the general formula [{RSi(µ-S)}2{ AuPPh3(µ-S)}2] which exhibit a central {Si2S2} four-membered ring.