Heteropolynuclear complexes with the ligand Ph2PCH2SPh: Theoretical evidence for metallophilic Au-M attractions

Addition of two equivalents of diphenylthiomethylphosphine (PPh2-CH2SPh) to the starting materials [Au(tht)(2)]A (tht = tetrahydrothiophene). AgCF3SO3 , or [Cu(CH3CN)(4)]CF3SO3 produces the mononuclear derivatives [M(PPh2CH2SP h)(2)]A (M = Au, A = CF,SO, (1a); M = Au, A = CIO, (1b); M = Ag, A = CF3SO3 (4); M: = Cu, A = CF3SO3 (5)) which are able to form the heterodinuclear c omplexes [AuM'(PPh2CH2SPh)(2)](CF3SO3)(2) (M' = Ag (2), Cu (3)) with a P-Au -P environment. If the starting gold complex is [Au(C6F5)(tht)], reaction w ith the phosphine produces [Au(C6F3)(PPh2CH2SPh)] (6) from whit reaction wi th AgCF3SO3 or [Cu(CH3CN)(4)]CF3SO3, the "snake" type linear complexes [Au2 M(C6F5)(2)(PPh(2)CH(2)Sph)(2)]CF3SO3 (M = Ag (7), Cu (8)) are obtained. If the silver starting complex is AgCF3CO3, reaction in a 3:1 ratio gives the tetranuclear complex [Au2Ag2(C6F5)(2)(PPh2CH2SPh)(2)(CF3CO2)(2)] (9). When the molar ratio is 1:2 the trinuclear complex [AuAg2(C6F5)(CF3CO2)(2)(PPh2C H2SPh)] (10) is obtained. According to ab initio calculations, the presence of only one gold atom is enough to induce metal-lophilic attractions in th e group congeners, and this effect can be modulated depending on the gold l igand.