Hanging a TV on the wall when it partially overlaps a window
This particular model provides a reach for the mounted television of a maximum of 29", which is astonishing (opinion) and according to the ad copy, allows a 90° turn for up to a 55" television set. This would appear to meet and exceed your requirements of about 45°. It's pricey, but not compared to the prices of large televisions that get knocked about.

As Tyson suggests, a Google search for "long reach wide television arm mount" would give you a wide selection. The one pictured above can be found here.