Pentacarba-arachno-tridecaalan (AlMe)8(CCH2Ph)5H mit Al8C5-Gerüst – das erste polyedrische Carbaalan

Abstract

Durch Hydroaluminierung von Aluminiumalkiniden gelangt man zur neuen Verbindungsklasse der Carbaalane. Der erste so erhaltene Cluster ist ein Pentacarbatridecaalan, das ein Al8C5‐Gerüst aufweist und aufgrund seiner Clusterelektronenzahl zu den arachno‐Verbindungen zu zählen ist (siehe Struktur).

New Carbaalanes Containing Clusters of Aluminum and Carbon Atoms: (AlEt)8(CCH2C6H5)5H, (AlMe)8(CCH2C6H5)5(C⋮C-C6H5), and (AlMe)7(CCH2CH3)4H2. Quantum Chemical Characterization

“…n -Pentane and cyclopentane were dried over LiAlH 4 ; toluene was dried over Na/benzophenone. Dimethylaluminum hydride, dimethyl(phenylethynyl)aluminum, diethylaluminum hydride, dimethylaluminum bromide, and the carbaalane 2 6 were synthesized according to literature procedures. Commercially available n -butyllithium (Chemetall) was used without further purification; propyne (Lancaster) was dried over P 4 O 10 prior to use.…”

“…In the course of these studies we also employed alkynyldialkylaluminum compounds and isolated crystalline products which had structures unprecedented in organoaluminum chemistry and which, owing to some similarities to carbaboranes, were named carbaalanes . The compound (AlMe) 8 (CCH 2 C 6 H 5 ) 5 H ( 1 ), obtained by the reaction of dimethyl(phenylethynyl)aluminum with dimethylaluminum hydride, contains a cube of eight aluminum atoms, five faces of which are bridged by C-benzyl groups and one face of which is bridged by a hydrogen atom. A total of 16 cluster electron pairs results, which is in accordance with an arachno configuration of the Al 8 C 5 cluster in 1 .…”

Synthesis, Structural Characterization and Reactivity of homo- and heterobimetallic Imidoalanes and Carbaalanes, Aluminum Hydrazide and Aluminum Peroxide Compounds

“…These aluminum-aluminum distances are comparable with those of the dimeric aluminum trimethyl. [180] The average bond angles are found to be similar to the reported carbaalanes [98][99][100][101][102][103]175,179] 77.29(17)°). Theoretical calculations [175] were done on 29 to understand the surface aromaticity and the nature of bonding within the core.…”

“…Only recently the field of polyaluminum chemistry became the subject of detailed research and in this pursuit Uhl and co-workers reported for the first time structurally characterized polyhedral carbaalane [(AlMe) 8 (CCH 2 Ph) 5 H] (2) by carrying out the hydroalumination reaction between excess of dimethylaluminum hydride and dimethylaluminum phenylacetylide. [98,99] It was formed by the repeated hydroalumination of the aluminum acetylide and by the condensation reaction with the simultaneous release of trimethylalane. The bridging hydrogen atom was introduced by a hydroalumination step with MeAlH 2 , which is formed by dismutation of Me 2 AlH.…”

Hydroalumination reactions on acetylenes and nitriles in the synthesis of carbaalanes and imidoalanes: an overview

“…Uhl and co-workers reported the structurally characterized polyhedral carbaalane (AlMe) 8 (CCH 2 Ph) 5 H (2) by carrying out the hydroalumination reaction between excess of dimethylaluminium hydride and dimethylaluminium phenylacetylide at 80 • C for 2 d (Scheme 1). 7,8 This compound was formed by the repeated hydroalumination of the aluminium acetylide and by the condensation reaction with the simultaneous release of trimethylalane. The bridging hydrogen atom was introduced by a hydroalumination step with MeAlH 2 , which is formed by dismutation of Me 2 AlH.…”