jupyter notebook --help-all
could be of help:
--notebook-dir=<Unicode> (NotebookManager.notebook_dir) Default: u'/Users/me/ipynbs' The directory to use for notebooks.
For example:
jupyter notebook --notebook-dir=/Users/yourname/folder1/folder2/
You can of course set it in your profiles if needed, you might need to escape backslash in Windows.
Note that this will override whatever path you might have set in a jupyter_notebook_config.py file. (Where you can set a variable c.NotebookApp.notebook_dir
that will be your default startup location.)