Add a new custom group to the site using Client Object Model

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Client;
namespace ClientObjectModel
{
class Program
{
static void Main(string[] args)
{
// Add a new custom group to the site
string siteURL = "http://serverName:1111/sites/SPSiteDataQuery/";
ClientContext context = new ClientContext(siteURL);
GroupCreationInformation groupCreationInfo = new GroupCreationInformation();
groupCreationInfo.Title = "Custom group";
groupCreationInfo.Description = " My Custom Group";
Group group = context.Web.SiteGroups.Add(groupCreationInfo);
context.ExecuteQuery();
}
}
}