Dialkylamides niobium

Homoleptic Nbv and Tav dialkylamides have been obtained (equation S).263,264 Extensive reduction, increasing with the length of the alkyl chain, was observed with niobium, the predominant products then being [Nb(NR2)4] (R = Et, Pr , Bun Section 34.3.5.4). Oxidation... 

Niobium and tantalum dialkylamides can easily undergo substitution or insertion reactions, as well as C—H activation. Substitution reactions have been used to obtain dialkylamides262 or dithiolenes.275 Aminolysis reactions, for instance, were assumed to occur via a simple associative mechanism (equation 6).276... 

The M-NR2 bond is labile and Nb and Ta dialkylamides M(NR2)5 (12) are valuable starting materials (Scheme 2). They can easily undergo substitution or Insertion reactions. Insertion of CO2, CS2, and COS in M(NR2)5 has been observed, giving dialkylcarbamates, dithiocarbamates, or monothiocarbamate derivatives, respectively. In the case of niobium, the insertion of CS2 is accompanied by reduction. Insertion of CO2 is catalyzed by amines resulting from adventitious hydrolysis. Monodentate as well as bidentate carbamato... 

Tantalum and niobium atoms were incorporated in the silaborate cluster by reaction of the dialkylamides with the silaborate 2. 

---