Enantioselective synthesis of tungsten trimetallic cluster chalcogenides

Abstract

Excision of {W 3 Q 7 Br 4 } n (Q = S, Se) of polymeric phases using chiral diphosphines is a general procedure to synthesize optically pure trinuclear clusters. Chiral transfer from the enantiomerically pure diphosphines (

C3-symmetry Mo3S4 aminophosphino clusters combining three sources of stereogenicity: stereocontrol directed by hydrogen bond interactions and ligand configuration

“…In both cases, the chirality of the diphosphine was preserved. [8][9][10][11] In order to explain the preferential diastereoselective formation of [Mo 3 S 4 Cl 3 (PPro) 3 ] + complexes, DFT calculations were performed to study the differences between relative energies among the four possible isomers. The calculated bond distances listed in Table 2 show a good agreement with the experimental data for the (P)-clusters (see Table 1 The calculated values for the dihedral angles that describe the conformation of the bicyclic system in the ligand are also in good agreement with the experimental data, with differences ranging less than three degrees.…”

“…This synthetic procedure was further extended to tungsten and selenium as well as to other optically pure diphosphines. [9][10][11] All these complexes combine the cluster framework chirality with that of the diphosphine ligand. In addition, these trimetallic Mo 3 S 4 compounds can act as metalloligands for a second transition metal to afford catalytically active chiral Mo 3 S 4 Cu clusters with moderate enantioselection in cyclopropanation reactions while preserving the absolute configuration of the cluster framework.…”

Synthesis and structure of methoxo-terminated molybdenum and tungsten M3S4 clusters containing aminophosphine ligands

“…[4] In the last years, our group has prepared a series of molybdenum and tungsten M3Q4 (Q = S or Se) clusters containing outer halide and diphosphine, aminophopshine, diamine or diimine ligands. [5][6][7][8][9][10][11][12][13][14][15][16][17] In the course of our work, difficulties arise when attempting to replace the terminal halide groups by hydroxo or alkoxo ligands due to cluster decomposition and/or oligomerization. In the case of the dmpe (1,2-bis(dimethylphosphino)ethane) derivatives, we have been able to isolate hydroxo-terminated [M3S4(OH)3(dmpe)3] + (M=Mo, W) clusters by taking advantage of the bulky characteristics of the diphosphane ligands which prevent them from decomposition.…”

Coordination Modes of Aminodiphosphane Ligands to the Cuboidal Mo3S4 Cluster Unit

“…[14,15] In contrast, functionalization with diphosphane, aminophosphane, diamine and diimine ligands takes place with one donor atom trans to the capping sulfur and the other trans to the bridging one resulting in chiral clusters with C3 symmetry, as depicted in Figure 1b. [7,12,13,[16][17][18][19][20][21][22][23][24][25] During the past years, research in our group has been devoted to the chemistry of chiral [Mo3S4X3(LL)3] + clusters derivatized with bidentate ligands containing phosphorous and/or nitrogen donor atoms. Up to date, a large number of complexes differing in the nature of the X ligands such as halide, pseudohalide, hydride, hydroxo, hydrosulphido, or alkoxo have been isolated.…”

“…Up to date, a large number of complexes differing in the nature of the X ligands such as halide, pseudohalide, hydride, hydroxo, hydrosulphido, or alkoxo have been isolated. [7,12,13,[16][17][18][19][20][21][22][23][24] Incidentally, the number of Mo3S4 derivatives bound to outer ligands coordinated in a tridentate fashion is limited to few examples Address correspondence to this author at the Department of Química Física i Analítica, Universitat Jaume I, Avda. Sos Baynat s/n, 12071, Castelló (Spain); Tel/Fax: +34964728086, +34964728066; E-mail: rosa.llusar@uji.es.…”