Synthesis and structures of bis(iminophosphorano)methanide chelate complexes with zinc and group 13

Bi- and tridentate coordination behaviour of a novel bis(phosphinimino)methanide ligand

Herein, we report the synthesis of a novel ferrocenyl-functionalized bis(phosphinimino)methane ligand (CH2 (PPh2 NFc)2 ). Deprotonation of CH2 (PPh2 NFc)2 with KN(SiMe3 )2 gave the dimeric species [K{CH(PPh2 NFc)2 }]2 , which was further reacted with ECl2 (E=Ge, Sn) to yield the tetrylene compounds [{CH(PPh2 NFc)2 }ECl]. The ligand and the resulting tetrylenes were examined for their electrochemical properties with the aid of cyclic voltammetry. Furthermore, the reaction of the tetrylenes [{CH(PPh2 NFc)2 }ECl] with [AuC6 F5 (tht)] resulted in the bimetallic complexes [{(AuC6 F5 )CH(PPh2 NFc)2 }ECl] with an unusual Au coordination on the ligand backbone.

Role of Bis(phosphinimino)methanides as Universal Ligands in the Coordination Sphere of Metals across the Periodic Table

The coordination chemistry of bis(phosphinimino)methanide ligands is widespread and accompanies a large number of metal ions in the periodic table ranging from lithium to neptunium. This unique class of ligand systems show copious coordination chemistry with the main-group, transition, rare-earth, and actinide metals and are considered to be among the most attractive ligand systems to researchers. The bis(phosphinimino)methanide metal complexes offer an extensive range of applications in various fields and have been demonstrated as one of the universal ligand systems to stabilize the metal ions in not only their usual but also their unusual oxidation states. The main-group and transition metal chemistry using bis(phosphinimino)methanides as ligands was last updated almost a decade ago. In this review, we provide a comprehensive overview of various state-of-the-art bis(phosphinimino)methanide-supported metal complexes by dealing with their synthesis, characterization, reactivity, and catalytic studies which were not included in the last critical reviews.

Phosphonium Ylides vs Iminophosphoranes: The Role of the Coordinating Ylidic Atom in cis-[Phosphine-Ylide Rh(CO)2] Complexes

The coordinating properties of two families of ylides, namely, phosphonium ylides and iminophosphoranes, differently substituted at the ylidic center (CH₂^- vs NiPr^-), have been investigated in structurally related cationic phosphine-ylide Rh(CO)₂ complexes obtained from readily available phosphine-phosphonium salt precursors derived from an ortho-phenylene bridge. However, while the Rh(CO)₂ complex bearing the P⁺-CH₂^- donor moiety proved to be stable, the P═NiPr donor end appeared to induce lability to one of the CO groups. All of the Rh^I carbonyl complexes in both ylide series were fully characterized, including through X-ray diffraction analysis. Based on the experimental and calculated infrared (IR) CO stretching frequencies in Rh(CO)₂ complexes, we evidenced that the phosphonium ylide ligand is a stronger donor than the iminophosphorane ligand. However, we also found that the difference in the intrinsic electronic properties can be largely compensated by the introduction of an iPr substituent on the N atom of the iminophosphorane, hence pointing to the noninnocent role of the peripheral substituent and opening novel possibilities to tune the properties of metal complexes containing ylide ligands.

Crystal Structures of Gallium(III) Halides with Bulky Ligands

Three oxygen donor gallium(III) halide complexes, [GaX3(O=P(TMP)3] (TMP = trimethoxylphenyl and X = Cl− (1), Br− (2) and I− (3)), are prepared by oxidation in mixed solvents from their phosphine adducts of [GaX3(P(TMP)3]. Three crystalline compounds are obtained from the solutions and their crystal structures are determined in the solid state. It is rare to generate a crystalline phase for metal–adduct compounds of this bulky ligand; in this paper, three new crystal structures are presented.