Aluminium Hydrazides: Reactions of tert-Butylaluminium Chlorides with Dilithium Bis(trimethylsilyl)hydrazide – Formation of Iminoalanes and their Hydrazido Adducts
✍ Scribed by Werner Uhl; Jens Molter; Rainer Koch
- Book ID
- 101281431
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 329 KB
- Volume
- 1999
- Category
- Article
- ISSN
- 1434-1948
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✦ Synopsis
Di(tert-butyl)aluminium chloride reacted with dilithium silyl)hydrazide with tert-butylaluminium dichloride gave, by complete cleavage of the hydrazido groups, a dimeric bis(trimethylsilyl)hydrazide with the formation of a novel Al 2 Li 2 N 4 cage compound 1. Its structure consists of a dimeric iminoalane [Me 3 C(THF)AlNSiMe 3 ] 2 (4), in which each aluminium atom is coordinated to one THF molecule. Its iminoalane RAl(µN-SiMe 3 ) 2 AlR (R = CMe 3 ), which is bridged by a dilithiumhydrazido ligand with an intact N-N bond. A uncoordinated, solvent-free form 5 was obtained by heating solid 4 to 150 °C in vacuo for several hours. It was identified heterocubane-type molecule is formed, in which two vertices are occupied by Al atoms, two by Li atoms and four by N as the tetrameric iminoalane (Me 3 CAlNSiMe 3 ) 4 , which does not adopt the expected heterocubane-type structure, but atoms. One face of the cube is strongly distorted due to the short N-N distance of the hydrazido group. A similar consists of three anellated four-membered Al 2 N 2 heterocycles in a kind of ladder structure. Remarkably, the compound, 3, was formed with bis(neopentyl)aluminium chloride but it was isolated in very poor yield. The reaction cage compound 1 could not be obtained by the reaction of an excess of lithium hydrazide with the iminoalanes 4 and 5. of Li 2 N 2 (SiMe 3 ) 2 with (Me 3 C) 2 AlCl in the presence of THF yielded an adduct 2, in which each Li atom of the cage is All compounds 1-5 were characterized by crystal structure determinations. additionally coordinated via Li-Cl-Al bridges to the ligand (Me 3 Al) 2 Cl•THF. The reaction of dilithium bis(trimethylproducts. [2Ϫ7] Recently, Nöth et al. synthesized a series of