400 hz is actually a common drive frequency for smaller sized motors that need to run at much higher RPM's than the standard 60 cycle VFD's run at.
However a 2.2 KW factory made VFD is cheaper to buy than build. I get them used on line a few times a year for under $100 with shipping.
You will never make one with all the features and abilities a standard off the shelf factory VFD has! I promise!
So standard 'how do I make an inverter' response applies here as well.
Just buy one. Its far better and will cost less than what you can make even a basic one for.