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7

Compare the results of your own theoretical considerations with the following solutions:

1. Number of resonance signals = 3

1 signal for the -OCH3- protons
1 signal for the -CH< - proton
1 signal for the -CH3 - protons
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2. Chemical shift of the resonance signals:

-OCH3 :        d = 3,3 .. 4,1 ppm
-CH(OR)2 :  d = 2,6 .. 5,3 ppm
-CH3 :           d = 0,6 .. 1,9 ppm
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3. Relative intensities of the resonance signals:

-OCH3 : 6
-CH< : 1
-CH3 : 3
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4. Line splitting due to spin-spin couplings:

-OCH3 : singulet
-CH< : quartet ( Intensities 1/8:3/8:3/8:1/8)
-CH3 : doublet ( Intensities 3/2:3/2 )
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5. Coupling constant

JCH - CH3 7Hz
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The theoretical spectrum should therefore look like this:
line spectrum
Now compare your line spectrum again with the actual spectrum