Terphenyl ligands

Scheme 13 Attempted synthesis of phosphaquinoid compounds carrying m-terphenyl ligand [13]...

With solubility as one of the principal problems to obtain structural information, the introduction of lipophilic ligands has been particularly successful, as shown impressively with the silyl substituted [CH(SiMe3)2] and [C(SiMe3)3] ligands.20 Steric bulk has also been applied successfully to reduce the tendency toward aggregation. This has been vividly demonstrated by recent chemistry utilizing terphenyl ligands.21... 

Attempts to prepare the lower aggregates have led either to higher aggregates or to disproportionated products. Nonetheless, use of the extremely bulky terphenyl ligand Ar = C6H3-2,6-Dipp2 allowed the first dimer of the type Ar SnSnAr to be... 

Element Derivatives of Sterically Encumbering Terphenyl Ligands... 

Fig. 1. Schematic representation of some currently used terphenyl ligands.

After the halide starting materials themselves, the alkali metal salts are the most important terphenyl compounds. This is a result of their widespread and almost exclusive use as transfer agents for terphenyl ligands. They can be synthesized by the simple reaction of n-BuLi with the halide (usually bromide or iodide). This general reaction,... 

The sole heavier alkali metal derivative of a terphenyl ligand is the compound (NaC6H3-2,6-Mes2)2.35 It was synthesized by the reaction of its lithium congener with... 

At present, only two organomagnesium derivatives of terphenyl ligands have been well characterized. However, the first terphenyl magnesium compound was reported more than 60 years ago with the generation of BrMgTriph in solution and its subsequent reactions to give the carboxylic acid, the acetyl derivative, and triphenylbenzophenone.28... 

Terphenyl ligands have also been utilized in the context of metalloporph-yrin chemistry. For example, the use of four Triph substituents at the periphery of manganese and iron porphyrin derivatives dramatically in-... 

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