Can someone give me the answers to the chemical shift of the protons in this compound: CH3CH2OCH2CH(CH3)COOH? Of if you can explain how to get the chemical shift it would be quite helpful as the info online does not really help me.
The protons in the ethoxy group will look nearly the same (triplet and quartet), and come in nearly the same positions, as they do in ethanol or diethyl ether or any ethyl ester.The next CH2 group will be a doublet, centered very near (perhaps very slightly downfield) overlapping with the quartet of the ethoxy group CH2.The CH group will be a multiplet (quartet of triplets, looks like grass) about 2.5, because it is next to a carbonyl group. Look at the spectrum of propionic acid for a good estimate, or isobutyric acid for an even better estimate.The alpha-methyl group should be a large doublet slightly downfield of a typical alkane methyl group. Somewhere about 1.0 or 1.1 would be a good guess. Again, look at isobutyric acid for an estimate.Learn to use Table 13-3 (Typical Values of Chemical Shifts) in the Wade text to estimate chemical shifts.
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