I like to place the recessed lights about 30" to 36" from the upper cabinets.
I like to space them about 4' to 5' apart....

It is also good to provide strip lighting underneath the upper cabinets to provide light on the counter tops.

The spacing of recessed cans depends on the lumen output of the bulbs allowed by the fixture ratings and the height of the ceiling. I go for about 300 lumens per linear foot of countertop on a 9' ceiling. You need more if the ceiling is higher as the foot-candles at the work surface decrease with more distance to the light source. Do not rely on under cabinet lighting for task lighting, it can only supplement it effectively. Too much under cabinet lighting is like preparing dinner in front of your car's headlights and leaves a shadow on the front side of whatever you are working on. I don't rely on more than 1/3 of the lumens coming from under the upper cabinets, and still use about 300 lumens/ft in the ceiling directly above the counter. Put the recessed lights where they don't cause shadows. The floor does not need to be the brightest place in the kitchen.