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Stepwise reduction of a base-stabilised ferrocenyl aluminium(iii) dihalide for the synthesis of structurally-diverse dialane species† † Electronic supplementary information (ESI) available: Synthetic procedures, NMR and UV-vis spectra, X-ray crystallographic and computational details. CCDC 2166939, 2166948, 2166949, 2166951, 2166952, 2166953 and 2166954. For ESI and crystallographic data in CIF or other electronic format see https://doi.org/10.1039/d2sc02783f

ABSTRACT: We report the reduction of bulky ferrocenyl-based NHC-stabilised aluminium(iii) diiodide [Fc*(NHC)AlI2] (Fc* = 2,5-bis(3,5-di-tert-butylphenyl)-1-ferrocenyl) in different hydrocarbon solvents (hexane, benzene, toluene, and p-xylene), which results in different outcomes. Reduction in hexane with an equivalent amount of KC8 generates the diiododialane [(Fc*(NHC)AlI)2], whereas complete reduction in hexane leads to an unusual C–H activation at an N–Me group of one NHC unit. In contrast, reaction in aromatic solvents result in hitherto unknown Birch-type reductions of the corresponding solvent molecules by transient aluminium radicals of the type [LAlR2]˙, which is ultimately bound to two aluminium centers. A bulky ferrocenyl-based NHC-stabilised aluminium(iii) dihalide was reduced in different solvents, leading to vastly different outcomes, including formation of a rare example of a dialane and a novel dialuminyl analogue of the Birch reduction.

SUBMITTER: Dhara D

PROVIDER: S-EPMC9400590 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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