Synthesis and reactivity of Pd(II) imidoyl complexes obtained by insertion of isocyanoferrocene into the Pd-C bonds of orthopalladated precursors.

While the multifaceted reactivity of organic isocyanides has been extensively demonstrated, that of their organometallic analogue, isocyanoferrocene (FcNC; Fc = ferrocenyl), has not yet been adequately explored. This contribution describes the syntheses of novel chelating Pd(II) imidoyl complexes, [(YCHCHC(NFc)-κ,)PdCl(PR)], by insertion of FcNC into the Pd-C bond of cyclopalladated precursors [(YCHCH-κ,)PdCl(PR)] (Y = MeN, MeS, R = Ph, Me). The imidoyl complexes underwent facile alkylation with [MeO][BF] to produce the cationic aminocarbene complexes [{YCHCHC(N(Me)Fc)-κ,}PdCl(PR)][BF].

Cyclopalladation of a ferrocene acylphosphine and the reactivity of the C-H activated products.

Acylphosphines are an attractive subclass of phosphine ligands with specific reactivity and ligating properties. This study describes the synthesis of a ferrocene-based acylphosphine, FcC(O)PPh (1, Fc = ferrocenyl), the corresponding phosphine chalcogenides FcC(O)P(E)Ph (E = O, S and Se), and palladium(ii) complexes resulting from the orthometallation of 1, viz. [Pd(μ-X)(1- H)] (2-X, where X = Cl, Br and I), which in turn serve as a convenient entry point to a range of monopalladium complexes.

Synthesis and characterisation of Pd(ii) and Au(i) complexes with mesoionic carbene ligands bearing phosphinoferrocene substituents and isomeric carbene moieites.

While numerous functional ligands combining phosphine and imidazole-2-ylidene (or imidazolin-2-ylidene) donor moieties have already been reported, the chemistry of the corresponding functional mesoionic carbenes (MIC) derived from 1,2,3-triazoles remains nearly untapped. This contribution describes the synthesis of two isomeric series of triazolium salts bearing 1'-(diphenylphosphino)ferrocenyl substituents by [3 + 2] cycloaddition of a P-protected phosphinoferrocene alkyne with azides, or alternatively of a P-protected phosphinoferrocene azide with terminal alkynes, and by subsequent methylation. These salts were used to synthesize structurally unique Pd(ii) complexes featuring a P,C-chelating triazolylidene carbene ligands and Au(i)-MIC complexes with free phosphine groups.