Further Examples of Simple, First-Order Spin Systems

4 Further Examples of Simple, First-Order Spin Systems 

With an understanding of simple first-order spin systems and of the Pople notations, we can consider the following example. 

The ring system, which has an axis of symmetry, consists of two interchangeable ortho, two interchangeable meta protons, and one para proton, all in the characteristic region for ring protons. The alert student, having absorbed the concept of chemical-shift equivalence, (Section 3.8.3) and the description of the 

FIGURE 3.34 Ethylbenzene in CDC13 at 600 MHz. The ethyl moiety is recognized by the CH3 triplet and the CH2 quartet. 

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