Synthesis of mono-, di-, and tri-arylgold(III) complexes using organomercury compounds - Synthesis of the first aurated Schiff bases

The formylarylmercury(II) complex [Hg{C6H(CHO)-6-(OMe)(3)-2,3,4)(2)] reacts with 4-butylaniline (1:2) to give [Hg{C6H(CH=NC6H4C4H9-4')-6-(OMe)(3)-2,3,4}(2)] (1) by a condensation reaction. This complex reacts with Me(4)-N[AuCl4] (1:1) to give [Hg{C6H(CH=NC6H4C4H9-4')-6(OMe)(3)-2,3,4}Cl] (2) and the monoarylgold(III) compound cis-[Au{C6H(CH=NC6H4-nBu-4')-6-(OMe)(3)-2,3,4}Cl-2]. (3). This complex reacts with PPh(3) (1:1) to give the adduct cis-[Au(C6H(CH=NC6H4-nBu-4')-6-(OMe)(3)-2,3,4) (4) and with AgClO4 (1:1) in acetone to give the ketonyl complex cis-[Au{C6H(CH=NC6H4-nBu-4')-6-(OMe)(3)-2,3,4}-{CH2C(O)Me}Cl] (5). cis-Me(4)N[Au(C6H4NO2-2)(2)Cl-2] reacts with [Hg{C6H3(N=NC(6)H(4)OMe-4')-2-(OMe)-5)Cl] and Me(4)NCl (1:1:1) to give cis-[Au{C6H3(N=NC(6)H(4)OMe-4')-2-(OMe)-5}(C6H4NO2-2)(2)] (6): Similarly, cis-Me(4)N- [Au(C6H4CF3-2)(2)Cl-2] (7), obtained by treating [Hg(C6H4CF3-2)(2)] with Me(4)N[AuCl4] and Me(4)NCl (1:1:1), reacts with [Hg(C(6)H(4)CH(2)NMe(2)-2)Cl] and Me(4)NCl (1:1:1) to give the triarylgold(III) complex cis-[Au(C(6)H(4)CH(2)NMe(2)-2) (C6H4CF3-2)(2)] (8). This complex can also be obtained by treating cis-[Au(C(6)H(4)CH(2)NMe(2)-2)Cl-2] with [Hg(C6H4CF3-2)(2)] and Me(4)NCl (1:1:1). The crystal structure of 3 reveals the presence of two independent molecules, in one of which the butylphenyl group is disordered. The geometry at the gold atom is square planar; distortions may be attributed to the narrow bite angle and steric repulsion between a chloride ligand and the ortho-methoxy group. The greater trans influence of the aryl ligand causes a great difference in Au-Cl bond lengths.