OK problem solved - I googled "how do I uninstall itunes" and was linked to an Apple page which showed procedure for this various elements of itunes had to be uninstalled in the correct order. Previously I only uninstalled itunes, but Apple Application Support, Apple Software Update, Apple Mobile Device Support and "Bonjour" all need to be uninstalled as well.

I then reinstalled itunes which invited me to restore my iphone to iOS 9.2.1. That done, the iphone was once again recognised by iprunes!!!