Synthesis and Characterization of Cp*Be-F-Al(O RF)3.

The reaction of Ag[Al(O RF)4] [ RF = C(CF3)3] with Cp*Be-Br was investigated. With the less basic CH2Cl2 as solvent, redox chemistry prevailed, elemental silver and the pentamethylcyclopentenyl cation (Cp*H2+) formed. However, upon changing to the more π-basic solvents fluorobenzene and o-difluorobenzene, the silver metathesis reaction went smooth and produced intermediately the [Cp*Be]+ cation and AgBr. However, the very strong Lewis acid [Cp*Be]+ activated one of the 36 equivalent C-F bonds of the [Al(O RF)4]- anion and finally formed two stable crystalline compounds containing the Cp*Be-F-Al(O RF)3 molecule, which includes a [F-Al(O RF)3]- anion coordinated to the [Cp*Be]+ cation. Cp*Be-F-Al(O RF)3 nevertheless includes some potential to provide [Cp*Be]+ in polar solution. Its potential neutral or ionic fission was investigated by DFT calculations. [ABSTRACT FROM AUTHOR]