Splitting Diagrams Explain the Multiplicity of a Signal

J chemical shift of the signal for the c proton if there were no splitting 

A splitting diagram for a doublet of doublets. The diagram begins with deb because J( j Jcij- 

A splitting diagram for a quartet of triplets. The number of peaks actually observed when a signal is split by two sets of protons depends on the relative magnitudes of the two coupling constants. 

The H NMR spectrum of 1-ohloro-3-iodopropane. The signal at 2.2 ppm is a quintet 8 instead of a triplet of triplets because = J c- 

Finding that the signal for the a protons is a quintet indicates that Jab and Jac have about the same value. The splitting diagram shows fhat a quintet results if Jab = Jac- 

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