Reactions of Tp∗-coordinated thiomolybdate and thiotungstate complexes with different silver salts

Abstract

Treatment of [Et4N][Tp∗MoS(S4)] (Tp∗=hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1a) with [Ag(MeCN)4]PF6 and PPh3 or Agdca (dca=dicyanamide) afforded two new neutral compounds [Tp∗MoO(μ–O)2MoO(μ–O)2MoO(μ–O)2OMoTp∗]·8(MeCN)0.5 (2·8(MeCN)0.5) and [Tp∗Mo(μ–S)(μ–S2)(μ–S3)MoTp∗]·DMF (3·DMF). Reactions of [Et4N][Tp∗WS3] (1b) with AgX (X=SCN, NO3, CN) in the presence of N- or P-donor ligands formed one binuclear cluster [Et4N][Tp∗WS(μ–S)2EW(NCS)2] (E=0.5O+0.5S) (4) and two W/Ag/S clusters [Tp∗WO(μ–S)2Ag(dppe)]·MeCN (5·MeCN) and [{Tp∗WS(μ–S)(μ3–S)Ag2(py)2}2(μ–CN)2] (6). These compounds were characterized by elemental analysis, IR, UV–Vis, 1H NMR and single-crystal X-ray crystallography. Compound 2 possesses a centrosymmetric tetranuclear structure in which two dinuclear [Tp∗MoO(μ–O)2MoO] units are linked by a pair of μ–O bridges. Compound 3 contains a dimeric structure in which two [Tp∗Mo] units are linked by one μ–S, one μ–S2 and one μ–S3 bridge. Compound 4 has another dimeric anionic structure in which one [Tp∗WS] unit and one [(SCN)2WE] unit are linked via a pair of μ–S bridges. Compound 5 has a dimeric structure in which one [Ag(dppe)]+ unit is linked by two μ–S atoms of [Tp∗WO(μ–S)2]− moiety. Compound 6 adopts a centrosymmetric hexanuclear structure in which two unique trinuclear [Tp∗WS(μ–S)(μ3–S)Ag2(py)2] units are interconnected by a couple of μ–CN bridges. The isolation of 2–6 provided an insight into not only the complexity arising from reactions of 1a and 1b with Ag(I) salts in the presence or absence of N- or P-donor ligands but also the interesting assembly chemistry of the Mo(W)/Ag/S clusters.