Poly(methylthiomethyl)Borates: A New Class of Sulfur-Rich Ligands for Metal Ions

Copper Complexes of Mono‐ and Ditopic [(Methylthio)methyl]borates: Missing Links and Linked Systems En Route to Copper Enzyme Models

“…One way to alter the donor/acceptor properties of scorpionate ligands over a wider range is to replace the pyrazolyl rings by phosphorus-(B [3][4][5] ) or sulfur-containing groups (C, [6,7] D; [8][9][10][11][12] Figure 1). Similar to the parent scorpionates A, ligands B-D provide a monoanionic, tridentate, face-capping coordination mode, but they differ from A with regard to the softness of their donor sets.…”

“…The H atoms have been omitted for clarity. Selected bond lengths [], bond angles [8], and torsion angles [8] (31)ÀB (1)ÀC (1) solid state; two crystallographically independent, centrosymmetric dimers constitute the asymmetric unit of the crystal lattice. Since both dimers have similar bond lengths and angles, only one of them will be described here ( Figure 6).…”

The Stability of Mercaptobenzothiazole Based Soft Scorpionate Complexes

“…While we can propose a reaction sequence which includes the formation of a  2 or  1 complex which promotes the ring closure and sulphur elimination (Scheme 1), structural analysis alone cannot provide any detail on the events occurring in solution and consequently we attempted to analyse these reactions using NMR methods. Thus the 1 H NMR spectra obtained from a solution of SbI 3 and NaTbz in d 6 -DMSO were recorded over two days at increasing time intervals. The broad resonances from NaTbz prior to addition of the SbI 3 are distinctive of this large anion where the rotation of the mercaptobenzothiazole groups about the B -N bond is slow on the NMR timescale ( Figure 5).…”

“…A schematic representation of the developments in scorpionate chemistry. From left to right: hydrotris(pyrazolyl)borate (Tp) (far left) [1,2]; the soft scorpionates hydrotris(methimazolyl)borate (Tm R ; R = Me, Ph, t Bu, etc)(centre left, top) [4,5] and hydrotris(mercaptobenzothiazolyl)borate (Tbz)(centre left, below) [9]; selenium and oxygen donor systems (centre right) [6,14,15]; and the poly(alkylthioalkyl)borates (right) [3,16]. The tetrakis(thioalky)borate anion (top right) was the first alternative soft donor system to be reported [3].…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] Not only has there been an increase in the range of heterocycles employed (benzoimidazole-2-thione, 6 1,3,4-thiadiazole-2-thione, 7,8 benzothiazole-2-thione, 9 thiazolidine-2-thione, 9,10 1,2,4-triazole-5-thione, 11 pyridine-2-thione, 12 pyridazine-2-thione 13 ) but the range of donor atoms has also expanded, with systems containing nitrogen, 1,2,6 , sulfur, [3][4][5][6][7][8][9][10][11][12][13] selenium, 14,15 oxygen 6 and phosphorus 16 donors (Figure 1) having all been reported. The chemistry being generated using these species is diverse, but within the reports on the complexes of soft scorpionates are results which suggest that in some circumstances these ligands may be prone to decomposition.…”