Syntheses and structures of [Re(SC6H3Me2-2,6)3(PPh3)], [Re(SC6H3Me2-2,6)3(ButNC)2], [Re(SC6H2Pri3-2,4,6)3L(PPh3)](L = N2 or CO) and [ReH4(PPh3)4][ReO(SC6H2Pri3-2,4,6)4]

Abstract

The hydride [ReH₇(PPh₃)₂] reacted with 2,6-dimethylbenzenethiol in toluene to give a complex of stoichiometry [Re(SC₆H₃Me₂-2,6)₃(PPh₃)]1. A crystal structure showed a trigonal-bipyramidal geometry about the Re with an agostic interaction to a thiolate methyl occupying an apical site, trans to the PPh₃ ligand. Complex 1 reacts rapidly with MeCN to give the known [Re(SC₆H₃Me₂-2,6)₃(MeCN)(PPh₃)]2 and with Bu^tNC to form [Re(SC₆H₃Me₂-2,6)₃(Bu^tNC)₂]3. The crystal structure of 3 showed trigonal-pyramidal geometry about the Re with asymmetric co-ordination of the isocyanide ligands and an unusual configuration for the thiolate aromatic groups. The reactions of the hydrides [ReH₇(PPh₃)₂] and [ReH₅(PPh₃)₃] with 2,4,6-triisopropyl-, 2,6-dimethoxy-benzenethiol and tris(2-sulfanylphenyl)phosphine were also studied. With HSC₆H₂Prⁱ₃-2,4,6 the dinitrogen complex [Re(SC₆H₂Prⁱ₃-2,4,6)₃(N₂)(PPh₃)]4 was formed and its structure determined. The preparations and structures of the complexes [ReH₄(PPh₃)₄][ReO(SC₆H₂Prⁱ₃-2,4,6)₄], [Re{SC₆H₃(OMe)₂-2,6}₃(PPh₃)] and [Re{P(C₆H₄S-2)₃}(PPh₃)] are also discussed. An alternative convenient route to [ReH₄(PPh₃)₄]⁺ from [ReH₅(PPh₃)₃] is presented.