Untitled

<html>
<head>
  <meta charset="utf-8">
  <title>add demo</title>

  <script src="https://code.jquery.com/jquery-1.10.2.js"></script>
</head>
<body>

<h1 class='Titulo'>Titulo</h1>

 <button title="Meu Novo Titulo">CLique aqui</button>

<script>

$('button').click(function(){

	var titulo = $(this).attr('title');

	$('.Titulo').text(titulo);
});

</script>

</body>
</html>