No, that will not work. The latest generation R2000 Claris groupset and it's predecessors are all 8 speed systems, so you can't select 11 sprockets on the cassette..
The 11 speed Ultegra derailleur isn't compatible with the 8 speed Claris group either. Shimano 11 speed road derailleurs have a different actuation ratio than 10 speed and below. (Actuation ratio is the ratio of cable length pulled to lateral movement of the derailleur cage.). Using an 11 speed derailleur with 8 speed shifters and cassette will give you trouble with indexing all the sprocket properly.
Shimano publishes extensive specifications and compatibility information you can consult to figure out what components work with each other https://productinfo.shimano.com/#/.