A new type of monoanionic “scorpionate” ligand. Synthesis, spectroscopic characterisation and dynamic behaviour of some niobium(III) complexes

Novel N,N,O Scorpionate Ligands and Transition Metal Complexes Thereof Suitable for Polymerisation

“…The additional IR band at ν = 1726 cm -1 is assigned to the asymmetrical carboxylate vibration of the methacryloyl ester. X-ray structure analysis of 6 confirms the formation of the bisligand complex [Cu(bdmpzmp) 2 ], but reveals a κ 2 -N,O coordination of 3, allowing a primary square-planar coordination of the copper centre ( Figure 5). The free octahedral positions are occupied by the oxygen atoms O3 and O3a of the methacryl linker.…”

“…The structures were solved by using direct methods and refined with full-matrix leastsquares against F 2 {Siemens SHELX-97}. [31] A weighting scheme was applied in the last steps of the refinement with w = 1/[σ 2 (F o 2 ) + (aP) 2 + bP] and P = [2Fc 2 + max(F o 2 ,0)]/3. Most hydrogen atoms were included in their calculated positions and refined in a riding model.…”

“…Reaction of the soluble deprotonated solid phase P1a with copper(II) chloride led to a deep-blue solid phase (P-Cu-I). The UV/Vis absorption maximum at 715 nm indicates the copper centres to act as crosslinking agent by a similar binding behaviour as in [Cu(bdmpza) 2 ]. In contrast, the heterogeneous reaction of P1b with copper(II) chloride formed a lime-green solid phase (P-Cu-II).…”

“…Bis(pyrazol-1-yl)acetic acids, such as bis(3,5-dimethylpyrazol-1-yl)acetic acid (Hbdmpza, 1) introduced 1999 by A. Otero, [1][2][3][4] are available in a broad variety of sterically less or stronger demanding, chiral and achiral ligands. [5][6][7][8] Complexes of these versatile N,N,O donor ligands with various transition metal complexes reveal their potential in coordination chemistry as scorpionate ligands closely related to hydrotris(pyrazol-1-yl)borate (Tp).…”

On the synthesis of heterocyclic dendrons

“…The solid residue was dissolved in dichloromethane and the solution was washed with water. The organic layer was dried with anhydrous Na 2 SO 4 (11). A mixture of 1,3,5-triethynylbenzene (0.167 mmol) and 1,3-bis(1H-1,2,4-triazol-1-ylmethyl)-5-iodobenzene (0.5 mmol) was introduced into a flame-dried 25 mL Schlenk tube under an inert atmosphere.…”