| 1. |
- Jonsson, Stefan, et al.
(författare)
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Synthesis of 2-pyridone-fused 2,2 '-bipyridine derivatives. An unexpectedly complex solid state structure of 3,6-dimethyl-9H-4,5,9-triazaphenanthren-10-one
- 2005
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Ingår i: Organic and Biomolecular Chemistry. - : Royal Society of Chemistry (RSC). - 1477-0539. ; 3:6, s. 996-1001
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Tidskriftsartikel (refereegranskat)abstract
- 2- Pyridone- fused 2,2'- bipyridine derivatives 1a and 1b were synthesised. X- Ray diffraction analysis of 1b revealed a highly complex solid state structure with a disordered molecule imbedded in a channel structure formed by a centrosymmetric lattice of hexagonally packed, hydrogen bonded columns. The columns are assembled from three symmetry independent molecules. Dimerisation of the self- complementary cis- amide hydrogen bond motif is overridden by the fulfilment of the proton coordination ability of the phenanthroline nitrogens in accordance with Etter's rules of hydrogen bond priorities.
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| 2. |
- Solano, Carlos, et al.
(författare)
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Introduction of aromatic and heteroaromatic groups in the 2-and 8-positions of the Troger's base core by Suzuki, Stille and Negishi cross-coupling reactions - A comparative study
- 2005
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Ingår i: European Journal of Organic Chemistry. - : Wiley. - 1434-193X .- 1099-0690. ; 2005:16, s. 3510-3517
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Tidskriftsartikel (refereegranskat)abstract
- A comparative study on the bis(functionalization) of the Troger's base core by aromatic and heteroaromatic groups using palladium-catalyzed cross-coupling reactions is presented. Three different reactions, the Suzuki, Stille, and Negishi couplings, were investigated using Troger's base analogues equally substituted in the 2,8-positions with (HO)(2)B, Bu3Sn and ZnCl groups, respectively, as the metallated comportent. Six aryl halides with different electronic and steric properties were employed as coupling partners. The presence of the bulky and electron-rich phosphane P(tBu)(3) as cocatalyst was found to play an important role. In addition, the palladium source, [Pd(PPh3)(4)] or [Pd-2(dba)(3)], was also found to be all important factor for the yield of the reactions, The Suzuki coupling was found to be the best method in general, giving excellent yields for most aryl halides, whereas the Stille and Negishi couplings gave moderate to good yields. Finally, the crystal structures of the 4-nitrophenyl- and the 2-pyridyl-appended analogues of Troger's base, 7d and 7f, are presented in the Supporting Information.
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| 3. |
- Solano, Carlos
(författare)
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TRÖGER´S BASE AS SCAFFOLD FOR SYNTHETIC RECEPTORS
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This work focuses on the use of the Tröger´s base as organic scaffold for the construction of synthetic receptors for different classes of organic molecules. The structural properties of the Tröger's base, i.e. chirality, rigidity and curvature, allow for synthetic modifications towards the recognition of different molecules. While the concave nature of the TB offers the geometrical frame for recognition events, the specific electronic properties of the appended binding motifs dictate the nature of the complementary molecules to be bound. In this way, the synthesis of different analogues of TB has allowed to study their affinity towards molecules as diverse as barbital, tris-L-alanine, alkyl bisammonium salts and fullerenes. This binding events have been quantified by means of NMR and fluorescence spectroscopy. Computational studies have been carried out to gain further understanding of the established interactions between the receptor and the substrate. The molecular recognition events have established the platform for the study of other processes. Thus, binding studies of different bisammonium salts have been used in an attempt to model the non-polar interactions between the aromatic side chains of natural receptors and lipophilic substituents of natural substrates. The sequential binding of metal ions to a bis-crown ether Tröger´s base analogue has been used to study the thermodynamic factors governing the observed negative cooperativity
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