Scorpionate hgands

This compound is polymeric with each scorpionate hgand bridging two thallium centers and the coordination environment approaching seesaw ... 

Owen GR, Gould PH, Charmant JPH, Hamilton A, Saithong S. A new hybrid scorpionate hgand a study of the metal-boron bond within metallaboratrane complexes. Dalton Trans. 2010 39 392-400. 

The Tp hgands (i.e., tris(pyrazolyl)borates or scorpionates [13]) are close analogs to the Cp hgands (i.e., -cyclopentadienyl), and in connection with the chemistry of the Tp Cr complexes mentioned above, a recent example of O2-binding from vanadium chemistry is of interest, even though it is formally not organometalhc chemistry Reaction of the V(IV) complex... 

Bnilding in parallel npon the discoveries of the lowering of the molecnlarity of [Ba(tmhd)2]3,4 by intermolecnlar addition of Lewis bases (see above), and of the isolation of monomeric clam-shell oligoether alkoxides (see below), the snccessfiil incorporation of intramolecnlar stabihty, in the form of a scorpion-taiT, on to the weU-known jS-diketonate hgand backbone was achieved. The synthesis of the first example of snch a ligand, Hdmmod (9), is a straightforward Claisen condensation (eqnation 41). While this procedure currently... 

Scheme 2.3 Examples of transition metal catalyst precursors for the peroxidative oxidation of alkanes, bearing (a) a C-scorpionate [16-20], (b) an azoderivative of a 8-diketone [21], (c) an aminopolyalcohol derivative (tea = deprotonated form of triethanolamine, Hjtea) [33, 34], and (d) a benzene dicarboxylate [33, 34] hgand.

After the initial writing of this chapter, some results were published. Ethene and carbon monoxide adducts of copper(I) with novel trispyrazolylborate Hgands ([HB(3-CF3-5- 4-RPh pz)3] R = N02, CF3, Cl, F, H, OMe, NMc2) in a pseudotetrahedral coordination environment consisting of three N atoms of the trispyrazolylborate ligand and the carbonyl or r -coordinated ethene ligands were found. The first scorpionate ligand... 

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