Imidotitanium Complexes with Heteroallylic Ligands: Synthesis and Solid-State Structure

Synthesis and Structure of Group 4 Iminophosphonamide Complexes

“…In the case of the unique structure of 4 , which features a PN 2 ligand substituted by N-TMS groups, the structure differs somewhat from those reported earlier …”

“…Given that 4 is actually an “ate” complex, in which the dimethylammonium counterion is H-bonded to one of the axial chloride ligands, it is not surprising that the Zr−N bond lengths are somewhat longer than in otherwise analogous neutral chloride complexes. Further, the PN 2 bite angle is narrowed because of this distortion, while the remaining metrical parameters associated with the PN 2 ligand are similar to PN 2 Zr compounds first characterized by Roesky and co-workers …”

“…Synthesis of PN 2 Ligands and PN 2 Complexes. A number of PN 2 complexes of the group 4 metals had been prepared and characterized prior to our work in this area; many of these compounds were synthesized by the reaction of an N , N , N ‘-tris(trimethylsilyl)-PN 2 ligand with the corresponding titanium or zirconium (IV) chloride . Monosubstituted complexes were generally accessible via this route and were typically dinuclear with halide bridges.…”

Neutral and Cationic Alkyl Tantalum Imido Complexes: Synthesis and Migratory Insertion Reactions

“…Nevertheless, treatment of early metal alkyl compounds with carbodiimides is a common method for the synthesis of amidinate complexes. − These types of reactions are usually performed with simple transition metal starting materials such as cyclopentadienyl or halide complexes. A two-step procedure involving the synthesis of a lithium salt of an amidinate ligand from a carbodiimide prior to a salt metathesis reaction with a metal−halide bond can also be used to synthesize amidinate complexes. , This method has previously been used to synthesize amidinate-coordinated titanium imido compounds. − Recently, however, the direct treatment of an alkyl titanium imido complex with diisopropylcarbodiimide has been reported to provide an amidinate complex . The similar transformation observed for compound 1 provides an efficient way to make tantalum imido complexes supported by amidinate ligands.…”

“…35,49 This method has previously been used to synthesize amidinate-coordinated titanium imido compounds. [54][55][56] Recently, however, the direct treatment of an alkyl titanium imido complex with diisopropylcarbodiimide has been reported to provide an amidinate complex. 57 The similar transformation observed for compound 1 provides an efficient way to make tantalum imido complexes supported by amidinate ligands.…”