Gold Clustering at Dimethylsulfoximine Me₂S(O)NH

Abstract

Gold Clustering, Dimethylsulfoximine Polyaurated complexes of the dimethylsulfoximide anion [Me2S(0 )N]_ have been prepared by reacting N-trimethylsilyl-dimethylsulfoximide with [(Ph3P)Au]BF4 in various molar ratios. With one or two equivalents of the gold(I) reagent only the dinuclear complex is obtained in high yield: {[(Ph3P)Au]2NS(0 )Me2}+ BF4-. With three or four equivalents only the trinuclear complex is produced: {[(Ph3P)Au]3NS(0 )Me2}2+ 2 BF4-.No mono-or tetra-auration was observed, respectively. The composition of the compounds has been confirmed by ana lytical and spectroscopic data, and the crystal structure of the dinuclear compound has been determined by single crystal X-ray diffraction of the dichloromethane solvate. The two gold atoms are found to be coordinated to the nitrogen atom with a small Au-N-Au angle of only 92.3(3)° and a short Au-Au distance of 2.9900(5) A. The nitrogen atom is in a distorted trigonal pyramidal configuration which allows an intramolecular SO-Au contact. For the trinuclear complex a structure with a tetracoordinate nitrogen atom [SNAU3] is proposed which is analogous to the corresponding complexes of phosphinimines R3P=NH. With the ditertiary phosphine Ph2PCH2Ch2PPh2 (dppe) a cyclic dinuclear complex (dppe)Au2[NS(0 )Me2]BF4 can be synthesized starting from (dppe)Au2C l2. The reaction of the phosphine-rich precursor [(Ph3P)2Au]BF4 with Me3SiNS(0 )Me2 in the molar ratio 2:1 affords a binuclear complex {[(Ph3P)2Au]2NS(0 )Me2}BF4 of an as yet unknown structure.

A briefing on aurophilicity

“…118 Two gold atoms can also be readily attached to the central carbon atom of carbodiphosphoranes (48). 119,120 Clustering of gold(I) cations has further been documented for the O-and S-atoms in gold alkoxides 121 and mercaptides (49), [122][123][124][125][126] as for the N-and P-atoms in primary amides, [127][128][129][130][131] diamides, 132 silylamides, 133 carbodiimides, 134 hydroxylamides (50), 135 phosphides, [136][137][138] phosphinimides (51), 139 and sulfoximides, 140 which give products of di-, tri-or even tetra-auration with one organic group at a vertex of the respective polyhedron. The oligomers of [AuSMe] n were the subject of DFT calculations and the structures of compounds with various ring sizes have been optimized.…”

New Chiral Benzothiazine Ligand and Its Use in the Synthesis of a Chiral Receptor

“…The variety of reactions containing sulfoximine-based ligands ranges from nickel-catalyzed asymmetric 1,4-additions to enones, palladium-catalyzed C-allylation, 1a, vanadium-catalyzed sulfide oxidation, copper-catalyzed Diels−Alder and hetero Diels−Alder reactions, copper-catalyzed 1,4-additions, copper-catalyzed Mukaiyama-type aldol reactions, and iridium-catalyzed imine hydrogenation 1b. The sulfoximine functional group continues to have promise as a convenient source of chirality that can be useful in catalytic reaction chemistry and stoichiometric chemistry 2 and shows promise in the development of materials for other applications …”