SFproG,
<!DOCTYPE HTML>
<html>
<head>
<title></title>
<style type="text/css">
.dv {width:300px; height:30px; border:solid 1px; margin:5px;}
</style>
</head>
<body>
<ul>
<li>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
<div class="dv">111</div>
</li>
</ul>
<script type="text/javascript">
var ul = document.getElementsByTagName('ul')[0];
var li = ul.getElementsByTagName('li')[0];
var fr = document.createDocumentFragment()
var n = 0;
while (li.children.length>3) {
n %=3;
if (n==0) {var li_new = document.createElement('li');
fr.appendChild(li_new)
}
li_new.appendChild(li.children[3]);
n++
}
ul.appendChild(fr)
</script>
</body>
</html>