Kitchen extract fan 60 l/s

[BiGAS]

Hi all,
Does anyone know of a 4" extractor fan capable of extracting 60 l/s?
I have checked many sites but can't find any, although I've been told they are available
The fan will be wall mounted on a small section of wall between a floor to ceiling fridge freezer and an external corner.
I reckon I have 200-250mm of brick before the stud and plasterboard.
If I need to fit a 6" duct, most fans are roughly 230ish mm wide. So even if fan was almost touching plinth on fridehe freezer, the 40mm each side of the 150mm (6") duct would mean the furthest edge of the duct will be 190mm from plinth.....very close to wooden stud.
A 4" fan would give me much more breathing space but I'm not seeing any.
Thanks in advance for any help.

 

[John D v2.0]

It will be incredibly noisy of you find one. There's a hell of a resistance on 100mm duct at 60l/s.
I'm having trouble understanding without a diagram, but can you fit a 5 or 6 inch inline decent fan and connect it to a 100mm duct (ideally two of them in parallel) . or rectangular duct, you can get 225x90 which is not much worse then 150 round.