using System;

using System.IO;

using System.Collections.Generic;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        var labelnames = @"[{'LabelName':'LabelName1','IsHeader':true},{'LabelName':'LabelName2','IsHeader':false},{'LabelName':'LabelName3','IsHeader':true},{'LabelName':'LabelName4','IsHeader':false}]";

        using (var sw = new StringReader(labelnames))

        using (var reader = new MyJsonTextReader(sw))

        {

            JsonSerializer ser = new JsonSerializer();

            ser.Deserialize<List<Label>>(reader);

        }

    }

    class MyJsonTextReader : JsonTextReader

    {

        public override char QuoteChar { get; protected set; } = '\'';

        public MyJsonTextReader(TextReader r) : base(r){}

    }

    class Label

    {

        public string LabelName;

        public bool IsHeader;

    }

}