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|3.3 NN-NHC-Ligand bbip: Toward Second Generation Catalysts| Table 13: Selected bond lengths [Å] and angles [°] of Ru(ip), Ru(bip), Ru(bbip), and Ru(bbip)Ag bond length [Å] or angle [°] Ru(ip) Ru(bip) Ru(bbip) Ru(bbip)Ag Ag1 - C13 - - - 2.080 (6) Ag1 - Cl1 - - - 2.3214 (16) Ru1 - N1 2.060 (4) 2.064 (5) 2.057 (4) 2.055 (5) Ru1 - N2 2.058 (4) 2.055 (4) 2.056 (4) 2.067 (5) N4 - C13 1.336 (8) 1.308 (7) 1.318 (7) 1.357 (9) N3 - C13 1.338 (8) 1.368 (7) 1.323 (7) 1.357 (9) N3 - C5 1.361 (7) 1.376 (7) 1.395 (7) 1.395 (7) N4 - C6 1.376 (7) 1.376 (7) 1.395 (7) 1.386 (7) C5 - C6 1.373 (8) 1.379 (8) 1.380 (8) 1.379 (9) N1 - C12 1.367 (7) 1.372 (7) 1.363 (7) 1.373 (7) N2 - C11 1.385 (7) 1.364 (8) 1.375 (7) 1.372 (7) C11 - C12 1.443 (8) 1.421 (8) 1.449 (7) 1.442 (9) C13 - Ag1 - Cl1 - - - 178.9 (2) N1 - Ru1 - N2 80.15 (17) 79.43 (17) 79.18 (16) 79.32 (19) N3 - C13 - N4 112.5 (5) 113.5 (5) 111.0 (5) 105.7 (5) C13 - N3 - C5 107.5 (5) 105.9 (5) 107.8 (5) 110.6 (5) C13 - N4 - C6 103.7 (5) 104.1 (5) 107.9 (5) 111.0 (5) N3 - C5 - C6 105.5 (5) 105.4 (5) 106.6 (5) 106.4 (5) N4 - C6 - C5 110.7 (5) 111.1 (5) 106.6 (5) 106.4 (5) N1 - C12 - C11 116.3 (5) 115.1 (5) 115.8 (5) 116.0 (5) N2 - C11 - C12 115.8 (5) 117.4 (5) 114.9 (5) 115.3 (5) The X-ray data indicated that the imidazole rings in Ru(ip) and Ru(bip) have identical C-N and C- C distances and equivalent bond angles at the analogical positions. A significant asymmetry with shortening of the C13-N4 bond with respect to the C13-N3 bond due to the partial double bond character in 1H-imidazoles is present in Ru(bip) (d Ru(bip) Ru(bip) (C13-N4) = 1.308(7) Å < d(C13-N3) = 1.368(7) Å). Furthermore, differences in the opposing C-N-C angles and N-C-C angles of the imidazole rings are present in Ru(ip) and Ru(bip) as well. Thus, both complexes exhibit by ∼5° wider N4-C6-C5 angles than N3-C5-C6 angles (e.g. ∠ Ru(bip) (N4,C6,C5) = 111.1(5)° > ∠Ru(bip) (N3,C5,C6) = 105.4(5)°). Additionally, Ru(ip) exhibits a more acute angle at the N3 atom when compared to the N4 atom (∠ Ru(ip) (C13,N3,C5) = 107.5(5)° > ∠Ru(ip) (C13,N4,C6) = 103.7(5)°). The N3-C13-N4 angles are the widest angles of |133|
|3.3 NN-NHC-Ligand bbip: Toward Second Generation Catalysts| the imidazole ring in both complexes (∠ Ru(ip) (N3,C13,N4) = 112.5(5)° = ∠Ru(bip) (N3,C13,N4) = 113.5(5)°). In Ru(bbip) and Ru(bbip)Ag, only insignificant changes of the bond lengths in the imidazole system were found when compared to Ru(ip) and Ru(bip). Surprisingly, the expected elongation of the C-C bond distances in the imidazolium salt and carbene complex were not observed. Nevertheless, a clear evidence of the increasing symmetry with extraordinary small deviations between the bond corresponding lengths (e.g. C13-N4 and C13-N3 or C6-N4 and C5-N3) and angles (e.g. N4-C6-C5 and N3-C5-C6 or C13-N3-C5 and C13-N4-C6) is present in Ru(bbip) and Ru(bbip)Ag. The N-C-N angles and C-N-C angles represent the mentioned changes in π-character and delocalization. Prominent is the stepwise decrease of the angle at C13 (∠ Ru(bip) (N3,C13,N4) = 113.5(5)° > ∠Ru(bbip) (N3,C13,N4) = 111.0(5)° > ∠Ru(bbip)Ag (N3,C13,N4) = 105.7(5)°) and the increasing angle at the N3 and N4 atoms (e.g. ∠ Ru(bip) (C13,N4,C6) = 104.1(5)° < ∠Ru(bbip) (C13,N4,C6) = 107.9(5)° < ∠Ru(bbip)Ag (C13,N4,C6) = 111.0(5)°). The C13-Ag1 distance (d Ru(bbip)Ag (C13,Ag1) = 2.080(6) Å) as well as the Ag1-Cl1 distance (d Ru(bbip)Ag (Ag1-Cl1) = 2.3214(16) Å) lie in the expected region for [Ag(NHC)Cl]-type complexes. Furthermore the expected linear coordination geometry is present (∠ Ru(bbip)Ag (C13,Ag1,Cl1) = 178.9(2)°) and no indication for a possible dimer formation was found in the crystal structure (For similar X-ray structures of [Ag(NHC)X]-type complexes (X = Br − /I − ) compare Roland, Alexakis et al. [186, 187] and Bouwman for dimeric complexes [188] ). Comparison of all ruthenium complexes with their corresponding ligands with respect to the imidazole ring shows nearly constant values for all distances and angles which is in accordance with a negligible influence of the coordination at the phenanthroline site. Only in the case of ip and Ru(ip) slight differences can be found which are most likely results of the protonation of ip in the crystal structure. As mentioned above, ip exhibits distances and angles which are rather consistent with the imidazolium salt Ru(bbip). In general, the structural features observed for Ru(ip), Ru(bip), Ru(bbip) and Ru(bbip)Ag combine both, the common patterns of other ruthenium NN-complexes and that of silver-NHCcomplexes and the prior imidazole derivatives respectively. 3.3.7 Preparation of bbip-Bridged Catalysts The main advantage of silver carbene complexes is their general applicability as carbene transfer agents which allows to transfer the coordinated NHC ligands to almost any kind of catalyst |134|
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Development of Novel Catalysts for
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Diese Arbeit entstand auf Anregung
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Den Arbeisgruppen von Prof. Dr. U.
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Contents 1 Introduction 1 1.1 Fossi
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|Contents| 6 Experimental Section 1
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|1 Introduction| 1 Introduction The
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|1.1 Fossil Fuels and Nuclear Power
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|1.2 Renewable Fuels| of natural ga
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|1.3 Energy Transformation and Stor
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|1.4 Solar Energy Conversion| A fra
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|1.5 Photosynthesis| Figure 9: Mole
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|1.6 Photocatalyzed Reactions| 2 NA
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|1.6 Photocatalyzed Reactions| (1)
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|1.7 Mimicking Photosynthesis| So t
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|1.8 Formalisms of Photocatalytic S
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|1.9 Multicomponent Systems from Fu
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|1.10 Intramolecular Photoredoxcata
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|2 Scope of the Thesis| motifs with
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|3.1 Brominated Phenanthrolines - A
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Page 185 and 186: |4 Summary| 4 Summary Against the b
Page 187 and 188: |4 Summary| The resulting complexes
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Page 191 and 192: |4 Summary| absorption between 430
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|5 Zusammenfassung| Die Herstellung
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|5 Zusammenfassung| phenphen und Ru
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|5 Zusammenfassung| Fragment tragen
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|5 Zusammenfassung| [TEA] + TEA vis
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|5 Zusammenfassung| In einer abschl
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|6 Experimental Section| Spectroele
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|6 Experimental Section| 1.3648 was
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|6.1 Synthesis of the Organic Ligan
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|6.2 Synthesis of the Metal Complex
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|7 Appendix| 7 Appendix dd ddd DEI
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|7 Appendix| Ru(tpphz)Os [Ru(bpy) 2
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|References| [26] M. Chanon, M. Sch
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|References| [81] S. Tschierlei, M.
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|References| [138] L. Pazderski, J.
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|References| [194] C. Liu, J. Li, B
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Selbstständigkeitserklärung: Ich
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