SYNTHESIS, STRUCTURE AND REACTIVITY OF [(ACAC)AUCH(PPH(2)AUPPH(2))(2)CHAU(ACAC)], A COMPLEX CONTAINING THE TRIDENTATE LIGAND [HC(PPH(2))(2)](-)

The complex [(acac)AuCH(PPh(2)AuPPh(2))(2)CHAu(acac)] (1) is obtained by various procedures: a) by reaction of [Ph(3)PAuCH (PPh(2)AuPPh(2))(2)CHAuPPh(3)](ClO4)(2) With NBu(4)[Au(acac)Cl], b) by reaction of [ClAuCH(PPh(2)AuPPh(2))(2)CHAuCl] with [Au(acac)PPh(3)] or with Tl(acac) and c) by reaction of [CLAuPPh(2)CH(2)PPh(2)AuCl] with Tl(acac). The acetylacetonato Ligand can act as deprotonating agent; thus, complex 1 reacts with (phosphane)gold complexes, [Au(C6F5)(2){(PPh(2))(2)-CH2}]ClO4, [Au(C6F5)(3)(PPh(2)CH(2)PPh(2))] or [AU(PPh(3))(2)]ClO4, to give the hexanuclear complexes [(C6F5)(2)Au{(PPh(2))(2)CH} AuCH(PPh(2)AuPPh(2))(2)CHAu{CH(PPh(2))(2)}Au(C6F5)(2)](ClO4)(2), [(C6F5)(3)Au(PPh(2)CHPPh(2))AuCH(PPh(2)AuPPh(2))(2)CHAu- (PPh(2)CHPPh(2))Au(C6F5)(3)] or [(Ph(3)PAu)(2)C(PPh(2)AuPPh(2))(2)C-(AuPPh(3))(2)](ClO4)(2), respectively. The crystal structure of 1 has been established by X-ray crystallography and displays two independent eight-membered rings with inversion symmetry and short transannular gold-gold contacts. The first ab initio results for a transannular Au-I-Au-I interaction are reported.