Die Hydroaluminierung von 1,1,4,4‐Tetramethyl‐2,3‐diazabutadien mit Dialkylaluminiumhydriden – Synthese von Dialkylaluminiumhydrazoniden |
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Authors: | Werner Uhl Jens Molter Bernhard Neumüller Fritjof Schmock |
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Abstract: | The Hydroalumination of 1,1,4,4‐Tetramethyl‐2,3‐diazabutadiene by Dialkylaluminium Hydrides – Synthesis of Dialkylaluminium Hydrazonides 1,1,4,4‐Tetramethyl‐2,3‐diazabutadiene reacted with dimethylaluminium hydride by hydroalumination of only one C=N double bond. The hydrazone derivative Me2Al–N(CHMe2)–N=CMe2]2 ( 1 ) was formed which gave a dimer possessing a six‐membered Al2N4 heterocycle. The hydroalumination of both C=N double bonds was not observed. Also an excess of di(tert‐butyl)‐ or bis(trimethylsilylmethyl)aluminium hydride afforded only the product of a single hydroalumination step, a second dialkylaluminium hydride molecule was attached via a coordinative interaction between its central aluminium atom and the nitrogen atom of the C=N double bond and in addition via a 3 c‐2 e Al–H–Al bond. Compounds (Me3C)2Al](Me3C)2AlH]N(CHMe2)NCMe2 ( 2 ) and (Me3SiCH2)2Al](Me3SiCH2)2AlH]N(CHMe2)NCMe2 ( 3 ) were formed which have five‐membered Al2N2H heterocycles. Thermolysis of 2 gave by C–H activation compound (Me3C)2Al]2CH2C(Me)=N–]2 ( 4 ) in trace amounts which possesses two anellated AlN2C2 rings with a common N–N bond. In contrast, the thermal decomposition of 3 yielded by the cleavage of the N–N bond a dimeric dialkylaluminium methylideneamide ( 5 ) which has two intact C=N double bonds. Up to now our attempts to insert a C=N double bond into an Al–C bond remained unsuccessful, and only the formation of an adduct (Me3C)3Al(–N=CMe2)2] ( 6 ) was observed upon treatment of tri(tert‐butyl)aluminium with the diazabutadiene derivative. |
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Keywords: | Aluminium Hydrazonides Hydroalumination Hydrides |
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