[OsmiumTetroxide]

The major product of reaction of furan with chloroform in presence of a strong base is an aldehyde.
Since Riemer-Tiemann reaction involves nucleophilic attack of carbanion on dichlorocarbene, CCl₂ gets attached to position 3 or 4. (This is because, the electron density at carbon near oxygen is reduced due to inductive effect)

Now, If pyrrole were to react with chloroform, these are the major products:

Why is there a difference in the products formed? Shouldn't dichlorocarbene attack position 3 or 4 for pyrrole as well?