(β-Diketiminato)dimethylgold(III): Synthesis, Structure, and Reactivity

Abstract

The reaction between [Me 2 AuCl] 2 and the lithium salt of a β-diketimine, [HC{C(Me)N(C 6 H 3 -2, 6-Me 2 )} 2 Li], yields the neutral Au(III) compound [HC{C(Me)N(C 6 H 3 -2,6-Me 2 )} 2 AuMe 2 ] (1). Compound 1 reacts with 1 equiv of triflic acid (HOTf) at -78 °C to provide the cationic AuTreatment of 1 with 2 equiv of HOTf results in the displacement of Me 2 AuOTf and formation of the β-diketiminato triflate salt [HC{C(Me)NH(C 6 H 3 -2,6-Me 2 )} 2 ][OTf] (3). Compound 1 reacts with I 2 to yield the cation [HC(I)-{C(Me)N(C 6 H 3 -2,6-Me 2 )} 2 AuMe 2 ] þ , which is isolated as the triflate salt [HC(I){C(Me)N(C 6 H 3 -2,6-Me 2 )} 2 AuMe 2 ][OTf] ( 4). The reaction of 1 with (PPh 3 )AuCl in the presence of AgOTf provides [HC(AuPPh 3 ){C(Me)N(C 6 H 3 -2,6-Me 2 )} 2 AuMe 2 ][OTf] (5). Molecular structures of 1, 4, and 5 were elucidated by single-crystal X-ray diffraction experiments; that of 4 was additionally confirmed by quantum-chemical calculations. The reactivity experiments indicate that the methine carbon in the β-diketiminato unit of 1 is the exclusive site of electrophilic attack, while the Au-C bonds are not perturbed.

Methyl Complexes of the Transition Metals

“…155 The agostic nature of the interaction of the bridging methyl was determined partly based on analysis of its JCH coupling constant, which, at ca. 125 Hz, according to the authors, was deemed significantly lower, than that found for other methyl fragments (135)(136)(137)(138)(139)(140). This was attributed to thermal averaging of the normal C-H coupling of ca.…”

On the non-innocence of “Nacnacs”: ligand-based reactivity in β-diketiminate supported coordination compounds

“…Scheme 43) 109,111,113,[183][184][185][186][187]. Overall, these remarkable examples demonstrate the coordinative versatility of the BDI ligands.Additionally, a variety of p-block electrophiles have been shown to react with (BDI)Li salts at the γ-carbon of the BDI backbone to form diverse structures of which selected examples are reproduced in Scheme 44 70,[188][189][190][191][192][193][194][195].…”

“…Substituting the γ-Me group by a γ-H leads to alkylation of the BDI γ-carbon and yields the corresponding cationic diimine complex featuring a C-C bond between a trityl fragment and the BDI gamma-carbon (Scheme 47bottom). 111 It is remarkable that in these last two examples the methine carbon of the BDI ligand is the preferred site of electrophilic attack compared to the Zn-Me and Au-Me bonds which remain inert. 111 It is remarkable that in these last two examples the methine carbon of the BDI ligand is the preferred site of electrophilic attack compared to the Zn-Me and Au-Me bonds which remain inert.…”

“…111 In the presence of 2 eq. i 0 2 , Ag(I), Ce(IV), or I 2 in presence of KPF 6 ; ii NEt 3 ; iii electricity, HNO 3 , HNO 2 , Cl 2 or I 2 ; iv NEt 3 .…”

Generation and Structural Characterization of a Gold(III) Alkene Complex

“…The AuÀC Me bond lengths in 3-BArf are 2.049(4) and 2.055(4) , quite typical for cationic Au III Me 2 fragments with relatively weak donor ligands trans to the methyl groups. [45,46] The structures of [(cod)AuMe 2 + ] and [(cod)PtMe 2 ], optimized at the DFT level with the hybrid PBE0 functional and quasi relativistic effective core potential (ECP) for Au (see computational details [47] ), indispensable for representing the structures and reactivity of Au complexes, [57,58] are in excellent agreement with the solid-state structures ( Table 1 and the Supporting Information). In particular, the calculations reproduce very well the nonequivalence of the two M À C cod bond lengths to the same C = C, and the larger difference between these distances for Au versus Pt.…”