Charles Yeager (www.yeagerfilm.com) shows how to create a 360 video without 360 footage. He uses Mettle SkyBox Studio in After Effects to build his 360 scene. He shoots himself against a greenscreen, and places the keyed 2D footage on top of an Element 3D cityscape.
To download a demo of SkyBox Studio (360/VR Plugin) for Adobe After Effects:
mettle.com/product/skybox-studio