Synthesis of 3-Diketimines and 3-Diketiminate Complexes

P Diketimines are prepared by the modification of classical organic reactions. In one case, the diketimines are formed from the diketone (Equation 4.48). The first step involves simple formation of an imine from the ketone and the amine. The second ketone is typically converted to an imine by alkylation of the oxygen to form a vinyl ether, followed by reaction of the resulting vinyl eflier with the second equivalent of amine. Alternatively, these ligands can be formed from the reaction of an arylamine, acid, and the p-diacetal of the diketone (Equation 4.49). Or, they can be prepared by addition of an alkyllithium or alkylpotassium reagent to two equivalents of nitrile, as shown in Equation 4.50.  

Transition metal p-diketiminate complexes are typically prepared by one of three routes. In one, these complexes are prepared by the reaction of a metal halide with an alkali metal P-diketiminate generated from the reaction of the p-diketiminate with an alkali metal base. An example of this synthesis is shown for the scandium system in Equation 4.51 In a second method, these complexes are prepared by the reaction of a transition metal complex containing a basic ligand, such as an alkyl or amido group, with the neutral p-diketimine. Two examples of this route for zirconium systems are shown in Equations 4.52 and 4.53, 3 

CHAPTER 4 covalent (x-TYPE) LIGANDS BOUND THROUGH METAL-HETEROATOM BONDS 

Transition Metal Complexes with Anionic Oxygen Ligands (Written with Prof. Pinjing Zhao) 

Many transition metal complexes contain anionic oxygen donor ligands, and many of these complexes display structures and reactivity that resemble that of more conventional organometallic compounds containing metal-carbon bonds. In some cases the alkoxo ligand is the site of reaction, and in other cases the alkoxide is an ancillary ligand. This section will focus on three main classes of compounds alkoxides (including aryloxides and the parent hydroxides), carboxylates, and p-diketonates. 

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