The following approach appears to work:
$('input[name="item_meta\\[180\\]"]').change(function(){
$('input[name="item_meta\\[640\\]\\[\\]"]').prop('checked',false);
});
Note that I removed the onclick
(since they weren't defined, their absence generated errors, and if you're using jQuery why are you even using in-line event-handlers?). Also, the escaping of the square-brackets (using the \\
characters).
References: