2380-36-1Relevant articles and documents
Synthesis and Reactivity of Iron Complexes with a Biomimetic SCS Pincer Ligand
Speelman, Amy L.,Skubi, Kazimer L.,Mercado, Brandon Q.,Holland, Patrick L.
supporting information, p. 1965 - 1974 (2021/02/01)
Recent experimental evidence suggests that the FeMoco of nitrogenase undergoes structural rearrangement during N2 reduction, which may result in the generation of coordinatively unsaturated iron sites with two sulfur donors and a carbon donor. In an effort to synthesize and study small-molecule model complexes with a one-carbon/two-sulfur coordination environment, we have designed two new SCS pincer ligands containing a central NHC donor accompanied by thioether-or thiolate-functionalized aryl groups. Metalation of the thioether ligand with Fe(OTf)2 gives 6-coordinate complexes in which the SCS ligand binds meridionally. In contrast, metalation of the thiolate ligand with Fe(HMDS)2 gives a four-coordinate pseudotetrahedral amide complex in which the ligand binds facially, illustrating the potential structural flexibility of these ligands. Reaction of the amide complex with a bulky monothiol gives a four-coordinate complex with a one-carbon/three-sulfur coordination environment that resembles the resting state of nitrogenase. Reaction of the amide complex with phenylhydrazine gives a product with a rare κ1-bound phenylhydrazido group which undergoes N-N cleavage to give a phenylamido complex.
The tris-urea motif and its incorporation into polydimethylsiloxane-based supramolecular materials presenting self-healing features
Roy, Nabarun,Buhler, Eric,Lehn, Jean-Marie
supporting information, p. 8814 - 8820 (2013/07/26)
Materials of supramolecular nature have attracted much attention owing to their interesting features, such as self-reparability and material robustness, that are imparted by noncovalent interactions to synthetic materials. Among the various structures and synthetic methodologies that may be considered for this purpose, the introduction of extensive arrays of multiple hydrogen bonds allows for the formation of supramolecular materials that may, in principle, present self-healing behavior. Hydrogen bonded networks implement dynamic noncovalent interactions. Suitable selection of structural units gives access to novel dynamic self-repairing materials by incrementing the number of hydrogen-bonding sites present within a molecular framework. Herein, we describe the formation of a tris-urea based motif giving access to six hydrogen-bonding sites, easily accessible through reaction of carbohydrazide with an isocyanate derivative. Extension towards the synthesis of multiply hydrogen-bonded supramolecular materials has been achieved by polycondensation of carbohydrazide with a bis-isocyanate component derived from poly-dimethylsiloxane chains. Such materials underwent self-repair at a mechanically cut surface. This approach gives access to a broad spectrum of materials of varying flexibility by appropriate selection of the bis-isocyanate component that forms the polymer backbone. Healing power: Easy access to a tris-urea motif, with the possibility of forming six H-bonds, has been demonstrated. This concept was further extended to the formation of soft functional materials based on polydimethylsiloxane moieties amenable to self-repair (see figure). Copyright
A new trigonal-bipyramidal [CuII(pytBuN3)Cl 2] complex: Synthesis, structure and ligand substitution behaviour
Shaban, Shaban Y.,Heinemann, Frank W.,Van Eldik, Rudi
experimental part, p. 3111 - 3118 (2009/10/17)
The synthesis, structure and ligand substitution mechanism of a new five-coordinate copper(II) complex with a sterically constrained pytBuN 3 chelate ligand [pytBuN3 = 2,6-bis(3,5di-tert- butylphenyliminomethyl)pyridine] are reported
