using System;

using System.Collections.Generic;

using AutoMapper;

using Newtonsoft.Json;

​

public class Program

{

    public static void Main()

    {

        var configuration = new MapperConfiguration(cfg =>

        {

            cfg.CreateMap<Item, Item2>();

        });

        var mapper = new Mapper(configuration);

        var collection = new ItemCollection();

        collection.Add(new List<Item>(){new Item{Name = "item"}});

        var dest = mapper.Map<List<List<Item2>>>(collection);

        Console.WriteLine(JsonConvert.SerializeObject(dest));

    }

}

​

public class ItemCollection : List<List<Item>>

{

}

​

public class Item

{

    public string Name { get; set; }

}

​

public class Item2

{

    public string Name { get; set; }

}

​