Methanide ligands

Simultaneously to the disclosure of 112-117 by Liddle, Le Floch reported that complex 88 could be converted to complex 121, which is analogous to 112-117, by reaction with potassium bis(trimethylsilyl)amide.48 The second deprotonation of one of the methanide ligands to give a methandiide-methanide complex is noteable because amides, especially silyl-amides, are not usually basic enough to effect a second deprotonation at a carbon centre (cf. synthesis of 1-8) and it was suggested that coordination to the electropositive neodymium polarised the C-H bond sufficiently to activate it. 

Monoanionic phosphine(phosphinimino)methanide ligands have recently been introduced in organolanthanide chemistry. Scheme 126 illustrates the ligand synthesis and the preparation of a Cp 2Sm(lll) derivative, which is monomeric in the solid state and contains the ligand in 3-heteroallylic fashion.583... 

SCHEME 5. Synthesis of a polynuclear gold complex containing bis(diphenylphosphino)methanide ligands... 

The non-innocent behaviour of the fcis(phosphinimino)methanide ligand [CH P(R2)=NR 2] provides an interesting way by which new and facile approach to new tripodal ligand systems. A novel example of this characteristic was recently illustrated by the reactions of [CH P(Ph2)=NSi-Mc3 2ZnR] [R=N(SiMe3)2 (29a), Ph (29b)] with BH3 thf. In the case of 29b... 

Several other studies have been reported on the utilization of P=N motif eontaining ligands. Thus, a titanium-imido complex (32) was stabilized by bis(iminophosphoranyl)methanide ligands. This complex undergos dynamic isomerization. Also, complex (32) displayed modest catal3rtic activity in the reaction of aniline with phenyl acetylene. ... 

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