I want such a tab/window to auto close in Safari:
One Moment Please.
Connecting to the iTunes Store.
If iTunes doesn't open, click the iTunes application icon in your Dock or Windows Task Bar.
I don't think you can. If you used an applescript it would also end up making Safari active. If your windows are arranged such that you can see the tab while iTunes is active you can hold down command and click on the close tab X and that will keep iTunes active while closing the tab in the background. That is about as close as you can get.