In-depth 27al NMR Investigation of Al(C6F5)3 and Its Complexes with Lewis Bases

For the first time, a correct 27Al chemical shift and W1/2 for 134 ppm Al(C6F5)3 as the most widely used Al-based ‘super-electrophilic’ Lewis acid was determined. A step-by-step proper way for acquisition and processing challenging 27Al spectra is suggested, which is applicable for any organo-aluminium compounds with asymmetric environment of Al. Using this procedure, several Lewis pairs of Al(C6F5)3 with N,O,S,P-centered Lewis bases were characterized.