Problem synching iPad with ITunes

I have an iMac 2.7 GHz Intel Core i5 operating on OSX 10.9.5, which I use to sync my iPad and iPhone to ITunes. It now freezes when I connect the iPad and I get a message "ITunes could not connect with iPhone. This device is no longer connected." Then I have to Force Quit to get out of the frozen iTunes. I need to sync a word processor app with the IMac, and this is now impossible. Any help will be grateful received.

Tony Knight