RESUMO
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(PPh2CH2SPh)2]A (M = Au, A = CF3SO3 (1a); M = Au, A = ClO4 (1b); M = Ag, A = CF3SO3 (4); M = Cu, A = CF3SO3 (5)) which are able to form the heterodinuclear complexes [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 with the phosphine produces [Au(C6F5)-(PPh2CH2SPh)] (6) from which, by reaction with AgCF3SO3 or [Cu(CH3CN)4]CF3SO3, the "snake"-type linear complexes [Au2M(C6F5)2-(PPh2CH2SPh)2]CF3SO3 (M = Ag (7), Cu (8)) are obtained. If the silver starting complex is AgCF3CO2, reaction in a 1:1 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(PPh2CH2SPh)] (10) is obtained. According to ab initio calculations, the presence of only one gold atom is enough to induce metallophilic attractions in the group congeners, and this effect can be modulated depending on the gold ligand.
RESUMO
The title compound, [Au(2)Cl(2)Fe(C(17)H(14)P)(2)], (I), contains the expected linear gold centres. The ferrocene moiety acts as a P, P'-bridging ligand, wherein the Fe atom lies on an inversion centre. The P-Au-Cl angle is 177.56 (8) degrees and bond distances Au-P and Au-Cl are 2.2261 (18) and 2.2781 (18) A, respectively. The structure is almost identical to that of the metal complex in (I).2CH(2)Cl(2) [Canales, Gimeno, Jones, Laguna & Sarroca (1997). Inorg. Chem. 36, 5206-5211], but differs considerably from that in 3(I).2CHCl(3) [Hill, Girard, McCabe, Johnson, Stupik, Zhang, Reiff & Eggleston (1989). Inorg. Chem. 28, 3529-3533], in that in the latter, the two independent molecules are linked by a short Au.Au contact.
RESUMO
A stereoselective synthesis of the disilyl derivatives 3 is achieved by the title reaction, an unprecedented Lewis acid promoted domino reaction, between the cross-conjugated dienone 1 and the allylsilanes 2. The configurations of the five stereogenic centers of this novel ring system are established in the first step of the reaction sequence, the double [3+2] cycloaddition.