Update list in different site collection using the API(cross domain)

<script type="text/javascript" src="https://code.jquery.com/jquery-1.11.0.min.js"></script>
<script type="text/javascript">  
    $(document).ready(function() {  
        var otherSiteUrl = "http://sp/sites/jerry";  
        var listName = "jerrylist";  
        var itemType = GetItemTypeForListName(listName);  
        var item = {  
            "__metadata": {  
                "type": itemType  
            },  
            "Title": "updated again"  
        };  
        // Get form digest value of the other site collection  
        $.ajax({  
            url: otherSiteUrl + "/_api/contextinfo",  
            type: "POST", //While trying to get Context info for user POST is used as type instead of method because body is empty while //request is sent   
            headers: {  
                "Accept": "application/json;odata=verbose"  
            },  
            success: function(contextData) {  
                console.log(contextData.d.GetContextWebInformation.FormDigestValue);  
                $.ajax({  
                    url: otherSiteUrl + "/_api/web/lists/getbytitle('" + listName + "')/items(1)?@target='" + otherSiteUrl + "'",  
                    method: "POST",  
                    contentType: "application/json;odata=verbose",  
                    data: JSON.stringify(item),  
                    async: false,  
                    headers: {  
                        "Accept": "application/json;odata=verbose",  
                        "X-RequestDigest": contextData.d.GetContextWebInformation.FormDigestValue,
                        "IF-MATCH": "*",  
                        "X-HTTP-Method": "MERGE"    
                    },  
                    success: function(data) {  
                        alert('success');  
                    },  
                    error: function(jqXHR, textStatus, errorThrown) {  
                        alert('error');  
                    }  
                });  
            },  
            error: function(jqXHR, textStatus, errorThrown) {  
                alert('error');  
            }  
        });  
    });  
    // Get List Item Type metadata  
    function GetItemTypeForListName(name) {  
        return "SP.Data." + name.charAt(0).toUpperCase() + name.split(" ").join("").slice(1) + "ListItem";  
    }  
</script>