I recently had a problem syncing my iPhone 5. It would get to step 2 and iTunes would freeze. I was able to do a backup but syncing purchased apps was impossible. After following every possible support forum post someone finally mentioned that the library might be corrupt.
I then went through the process of creating a new library. When you recreate your library it will forget everything that is synced to your iDevices but it will still recognize the devices themselves. You will need to make sure they are in a good state so that you can sync them back to the computer.
Change the Library used by iTunes – Hold CTRL key when launching the application.
Run iTunes in Safe Mode – Hold CTRL+SHIFT