You are listing each file, removing the extension, then trying to move that filename.
The extension is part of the filename, don't remove it. Windows Exlorer hides the extension only when displaying files.
You also don't need to call os.chmod()
on the filename; just skip that step:
for file in files:
filename = os.path.splitext(file)[0]
print filename
shutil.move(filename, result_dir)