I know that NBS is a selective brominating agent especially on the allylic position. And its reaction mechanism is of free radical.
But I can't figure out the reason for the change in position of the double bond in the products.
It would be helpful if someone could give the mechanism along with its reason.
This is what I'm thinking, that might be happening there but still I don't understand how and why something like this would happen.
My mistake, number 3 and the product which I have marked as not formed are same.
2)Which one among these three products is the major product?