Config Sass to output to a different folder in Ionic 3

I’m in need of your knowledge and help, this is what I’m trying to achieve:

I’m currently using Ionic 3. I have an example.scss currently at src/theme/example.scss.

I know that I need to override webpack’s config, so I copied webpack.config.js and sass.config.js to /config at my proyect’s root folder.

I need to specifically ‘tell’ webpack to compile src/theme/example.scss to build/example.scss

I’ve read a lot about webpack, but I can’t seem to find how to make it compile an specific file to a specific folder. Is it posible?

Hope you guys can help me!