Possible duplicate: Same problem (unresolved)
I show loading DOM before the Ajax call and after the Ajax call, I hide it. For some reason, the loading image appears
I know Im a bit late to the party on this, but for future reference if you want to have a loading animation AND use a synchronous ajax call AND have it animate in chrome, you can use this third party ajax script: http://fgnass.github.io/spin.js/#!
Spin.js dynamically creates spinning activity indicators that can be used as resolution-independent replacement for AJAX loading GIFs.
I use it extensively and it works perfectly for me.