Spin aluminium compounds

Table tt. l-ii Z Spin-orbit splitting energies of aluminium compounds... 

The highly characteristic chemical shifts of the ring carbon atom in arenium ions and the spin-spin interaction of carbons and other elements with magnetic nuclei are widely used in establishing the structure of new ions. An example is the corroboration of the bipolar structure in the complexes formed from phenols and aluminium halides and proving the structure of the ions generated by the interaction of polymethylated aromatic compounds with heteroatomic electrophilic reagents (see... 

Electron spin resonance (ESR) spectra have been used to detect and characterise some paramagnetic ionic compounds which exist as intermediates. An example is l,l,4,4-tetrakis(trimethyl-silyljbutatriene [662] which can be detected only in anionic or cationic form. The anion is obtained with metallic potassium in diethyl ether at 20 °C, and the cation with aluminium chloride in dichloromethane at — 50 to — 70 °C. 

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