When exploring the general chemical reactivity of 15, we found that saponification conditions unexpectedly led to the formation of the rearranged homoannulene carboxylic acid 16 (for a proposed mechanism, see the Supplementary Figure ). This turned out to be a fortunate discovery, as 16 not only represents yet another neutral homoaromatic compound, but with the X-ray crystal structure of 16 available, it also serves as key reference compound for the following investigation of the magnetic properties of the neutral homoaromatics 15 and 16. Homoannulene ester 15 and the rearranged homoannulene carboxylic acid 16 turned out to be ideal probes for the investigation of magnetic properties (induced ring current) indicative for a homoaromatic interaction . Magnetic anisotropy and susceptibility of homoaromatic compounds is verifiable by NMR spectroscopy through marked chemical shifts . Comparing the 1 H NMR spectra of 14a, 15 and 16 (Fig. ), we observed that 15 and 16 display a significant down-field shift of hydrogen atoms 5 and 6 of ~1.00 ppm as compared to 14a, giving a first indication of the presence of a ring current in the former two.