Two Isomers with an Al4C8 Framework

✍ Scribed by Christoph Üffing; Achim Ecker; Ralf Köppe; Kurt Merzweiler; Hansgeorg Schnöckel

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 156 KB
• Volume: 4
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/(sici)1521-3765(19981102)4:11<2142::aid-chem2142>3.0.co;2-1

✦ Synopsis

The co-condensation, by annealing from À 196 8C to room temperature, of the high-temperature species AlCl and 3-hexyne (EtCCEt) with an excess of toluene leads to the formation of the compound (AlCl ´EtCCEt) 4 . Characterisation by X-ray analysis revealed the presence of two isomers in the same crystal: a dimeric 1,4-dialumina-2,5-cyclohexadiene and a 1,4,7,10-tetralumina-2,5,8,11-cyclododecatetraene. Both isomers exhibit aluminium ± olefin p-bonding, with the Al 4 entities present in a tetrahedral arrangement. The bonding in both isomers is discussed on the basis of ab initio calculations performed for model compounds.