Given the following information, predict the appearance of the 1H NMR spectrum arising from the vinyl hydrogen atoms of p-chlorostyrene. Deshielding by the induced magnetic field of the ring is greatest at proton c (δ 6.7) and is least at proton b (δ 5.3). The chemical shift of a is about δ 5.7. The coupling constants have the following approximate magnitudes: Jac ( 18 Hz, Jbc ( 11 Hz, and Jab ( 2 Hz. (These coupling constants are typical of those given by vinylic systems: coupling constants for trans hydrogen atoms are larger than those for cis hydrogen atoms, and coupling constants for geminal vinylic hydrogen atoms are very small.)

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(c) (b) H a) iA CI