(a) Verify that the following compound meets the Hckel criteria for aromaticity. (b) The NMR spectrum of...

(a) Verify that the following compound meets the Hückel criteria for aromaticity.

(b) The NMR spectrum of this compound consists of two sets of multiplets: one at δ 9.28 and the other at δ (22.99); the latter resonance is at 3 ppm lower chemical shift than that of TMS—that is, to the right of TMS in a conventional NMR spectrum.

The relative integral of the two resonances is 2 : 1, respectively. Assign the two sets of resonances, and explain why their chemical shifts are so different; in particular, explain why one of the chemical shifts is so small. 

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Η Η. Η --- Η. H H Η -- H H Η Η H Η. Η Η H H H H inner protons outer protons