BLDC : Only half of its coils is active
Theoretically it could work, if you know what remains. Three coils should be enough. It will be like a linear motor, just bent to a circle. 

But there will be uncompensated force on the rotor in direction perpendicular to it, bearings will suffer.

Although on your picture it looks like the rotor is outside. What are you going to put instead of the coils?