public static void RegisterRoutes(RouteCollection routes)

{

     ModelBinders.Binders.Add(typeof(JObject), new JObjectModelBinder());

}

public class JObjectModelBinder : IModelBinder

    {

        public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)

        {

            var stream = controllerContext.RequestContext.HttpContext.Request.InputStream;

            stream.Seek(, SeekOrigin.Begin);

            string json = new StreamReader(stream).ReadToEnd();

            return JsonConvert.DeserializeObject<dynamic>(json);

        }

    }