Enol content tautomers
Enol content in 3 is greater then enol content of 2


Greater the acidic nature of alpha Hydrogen,greater is the tendency for Tautomeric behavior. H at alpha position in ketone is more acidic then H at alpha position in an ester.Pka values are shown below.The withdrawing power of ester is less compared to carbonyl group in ketone. Since lone pair on oxygen is in conjugation with C=O in ester,its withdrawing power decreases(as shown below).A more acidic α-hydrogen implies a weaker C−H bond. Summarizing,the enol content increases with the acidity of the enolic hydrogen. 

$$\ce{carbonyl &lt;=&gt; enol}$$
$$\mathrm{K_{eq}=\frac{[enol]}{[carbonyl]}}$$

The equilibrium between keto and enol form is tipped to enol if H at alpha carbon is more acidic.

Hence enol content in 3 is greater then enol content of 2.

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  Pka of cyclohexanone is as per this link: https://www.drugbank.ca/drugs/DB02060


Enol of 4th compound is aromatic and should be most stable.

Therefore extent of enol content must be 4>1>3>2.
As a general guide line the following can be used for predicting enol content.





The enol form of cyclohexanone  has bond angles around double bond other then 120${^o}$ as shown below using avagadro.