N,O-Polydentate Scorpionate Ligands

Abstract

New bis- and trispyrazolylborate (scorpionate) ligands derived from 3-(2,4-dimethoxyphenyl)pyrazole have been synthesized. They can function as N,O-polydentate donors, as was demonstrated in the structure of the octahedral complex Ni[Bp(2,4(OMe)2Ph)]2. The structure of Tl[Tp(2,4(OMe)2Ph)] has also been determined.

Synthesis, molecular structure, and photoluminescence properties of palladium and platinum complexes containing phosphine sulfide-based SCS pincer ligand

“…6(18) result in lengthening of the P Ä/S bond length compared with the range of free P Ä/S bond length [3,4,8]. A similar feature was observed with 3.…”

Copper(I) Complexes of Naphthyl‐Substituted Fluorinated Trispyrazolylborate Ligands with Ethene and Carbon Monoxide

“…[9] The presence of multiple conformational isomers was not observed in the NMR spectra of the copper complexes of [Tp CF3,1Nt ] -. [9] The presence of multiple conformational isomers was not observed in the NMR spectra of the copper complexes of [Tp CF3,1Nt ] -.…”

“…The "forward" facing substituents on the 3-position of the pyrazolyl groups are typically altered to modify the chemistry in the direct vicinity of the metal center coordinated by the ligand. [2,[5][6][7][8][9] By reducing electron density on the copper(I) ion electron-withdrawing substituents like trifluoromethyl and nitro groups on the pyrazolyl rings of scorpionate ligands oxidatively stabilize the Cu I oxidation state. Typically the most bulky substituents will assume the 3-positions in the scorpionate ligand unless there is a strongly electron-withdrawing substituent in the opposite position of the pyrazole ring, in which case the more bulky substitu-[Na 2 (Tp CF3,1Nt ) 2 (μ-acetone) 2 ] is found in a distorted octahedral coordination geometry formed by three N-donors of the facially coordinating tridentate ligand, two O-donors of bridging acetone ligands and a fluoride of a bridging -CF 3 group with a particularly short Na···F distance.…”

Synthesis and Properties of Poly(pyrazolyl)borate and Related Boron-Centered Scorpionate Ligands. Part A: Pyrazole-Based Systems

“…23, (e)). 24, (a)) [167,168], or in the potentially hexadentate ligands tris [3- [HB((2,4-(OMe) 2 Ph)pz) 3 ] - [170]. Lower denticity, such as 1 -N, has been also reported (Fig.…”