Aluminum amidinate complexes

Aluminium amidinate complexes 392 are synthesized by addition of aluminum alkyls to aliphatic carbodiimides. Also, alkylation of carbodiimides with MeLi, followed by reaction with AICI3 affords aluminum amidinate complexes... 

The polymerization of methyl methacrylate (MMA) by Cu(ll) amidinate complexes (Scheme 222) in combination with alkyl aluminum complexes has been reported. The preferred alkylating agent is methylalumoxane (MAO) in... 

Figure 53 Energy barrier upon conformational change or cation exchange in the complex of neutral and cationic aluminum amidinates.

The coordination chemistry of ancillary amidinate ligands with a pyridine functionality has been described. Magnesium, aluminum, zirconium, and lanthanum complexes have been prepared in which the amidinate anions act as tridentate, six-electron-donor ligands Amidinate ligands containing quinolyl substituents were constructed in the coordination sphere of lanthanide... 

Figure 21 Examples of aluminum complexes of phenyl hydrazones and amidines.

Allyltetramethylphosphorodiamidate, 5 N-Allylthioamides, 31 Allyltin difluoroiodide, 6, 374 ir-AUyltifanium complexes, 131 Allyltrimethylsilane, 1,6-8 AUyltrimethylsilylzinc chloride, 8 Allyl vinyl ethers, 157 Alumina, 8-9, 335 Aluminum chloride, 9-11, 262 Aluminum chloride-Ethanethiol, 11 Alluminum telluride, 205 Amidines, 347-348 a-Amino alcohols, 10 (3-Amino alcohols, 3, 117-118, 381 7-Amino alcohols, 236-237 4-Amino-2-azabutadienes, 157... 

Benzamidines aluminum complexes were prepared, by adding benzoyl chloride to a mixture of 10% NaOH and 2,6-diisopropylaniline followed by chlorination with thionyl chloride and treatment with aryl amine yielded the corresponding amidine compounds, further reacting with AlMe to form 37-42 complexes (Scheme 6.8) [53]. The X-ray diffraction analysis shows that the complex 38 is monomeric with distorted tetrahedral geometry at the aluminum center (Figure 6.2) [53],... 

Traditionally, aluminum alkoxides have been used as homogeneous catalysts for the Tishchenko reaction. Other catalysts such as boric acid and a few transition-metal complexes have also been used. However, these catalysts are either reactive only imder extreme reaction conditions or very slow. Recently, great effort has been focused on the development of organolanthanide complexes as catalysts because of their high Lewis acidity, easily tunable coordination sphere around the metal, and environmentally friendly property. Series of organolanthanide complexes, such as alkyls, amides, and amidinates, were found to be highly efficient catalysts for the Tishchenko reaction. The proposed catalytic mechanism is provided in Scheme 11, and the precatalyst reacts with aldehyde to give lanthanide alkoxide as the catalytic active species. 

---