Automate file name change to specific name

Is there a way to automate the name change of a file placed in a folder to a specific file name and remove the original name?

For example an image is moved to a folder called "image1.jpg" and as soon as its moved into a folder its renamed to "chapter1a.jpg"

 

I know through automations how to add the chapter1a but not to remove the original file name so it comes out as chapter1aimage1.jpg

 

Any ideas on how to do this. - I assume its an easy fix??