Well it can be achieved with bridge edgesBridge Edge Loops function:
align end capAlign 'end cap' polygons at the beginnings of the desired curve. The trick is to maintain same distance from the angle point.
selectSelect both caps. Press W and press -> select Bridge edge loops.W > Bridge Edge Loops
tweakTweak connection properties
[![Caps aligned with tangent points][1]][1] [1]: https://i.sstatic.net/uV1gP.png