How to escape whitespace in variable passed to cd

I am using WSL on windows 10 with Ubuntu.
The path to a directory I use frequently includes a directory with a space in the name. I can't change that name. The path to the directory is very long:
/mnt/c/Users/name/Dropbox/My PC (Laptop...)/Desktop/Studies/Python
So I would like to create a variable in .bashrc by the name of $PROJECTPATH that would be equal to the directory's path.
That way I could call or alias cd $PROJECTPATH and get to my files.
I tried writing:

PROJECTPATH='/mnt/c/Users/name/Dropbox/My\ PC\ \(Laptop...\)/Desktop/Studies/Python'

alias prjct='cd $PROJECTPATH'

but when running prjct I'd get the error message "too many arguments" which means there's a space being passed to cd.
How could I escape whitespaces when passing a variable to cd or any other command?
And should I export this kind of variable?

You need to put double quotes around $PROJECTPATH in your alias definition.

Also, I recommend against backslashes in your variable definition. It's less readable and isn't needed in this case:

PROJECTPATH='/mnt/c/Users/name/Dropbox/My PC (Laptop...)/Desktop/Studies/Python'

alias prjct='cd "$PROJECTPATH"'