using System;

using System.Collections.Generic;

using System.Linq;

using Newtonsoft.Json.Linq;

public class Program

{

    public static void Main()

    {

        var obj = new List<dynamic>()

        {

            new Dictionary<string, string>()

            {

                { "Id", "13" },

                { "Name", "SpecialCollections" },

                { "Seo", "{\"SeoUrl\":\"special-collections\",\"SeoPageTitle\":null,\"SeoKeywords\":null,\"SeoDescription\":null}" }

            }

        };

        JArray ja = new JArray(

            obj.Select(

                dict => new JObject(

                    ((Dictionary<string, string>)dict).Select(

                        kvp => new JProperty(kvp.Key, ToJToken(kvp.Value))

                    )

                )

            )

        );

        string json = ja.ToString();

        Console.WriteLine(json);

    }

    private static JToken ToJToken(string s)

    {

        if (s == null)

            return JValue.CreateNull();

        // if the string is already JSON, parse it into a JObject (or JArray)

        if ((s.StartsWith("{") && s.EndsWith("}")) || (s.StartsWith("[") && s.EndsWith("]")))

            return JToken.Parse(s);

        // otherwise create a JValue from the non-JSON string

        return JToken.FromObject(s);

    }

​

}