Run the command chmod the file permissions www-data: www-data inside the jailkit

[buhlerax]

I have a php application that needs to run on mod-php, is even faster.
The permissions of the client's domain is web7: client6.
The problem is that the user created for shell access is web7: client6 and can not chmod files in php script that creates the web folder.
The scritp are an owner and does not allow modifications. And because of the mod-php everything is recorded as www-data: www-data.
I can do for this specific user shell access web7: www-data?
There is another way around this?
I've tried several things without success. Even setting group, user and sudo command within the jailkit.
thank you