class MyClass
{
    public string email {get; set; }
    public string status { get; set; }
}

List<MyClass> data = new List<MyClass>();
data = MagicallyGetData();

string json = new {
     operations = new {
          JsonConvert.SerializeObject(data.Select(s => new {
               email_address = s.email,
               status = s.status
          }))
     }
};

{
  "operations": [
    {
      "email_address": "email1@email.com",
      "status": "good2go"
    },
    {
      "email_address": "email2@email.com",
      "status": "good2go"
    },...
  ]
}

class MyClass
        {
             public string email_address { get; set; }
             public string status { get; set; }
        }

        List<MyClass> data = new List<MyClass>() { new MyClass() { email_address = "email1@email.com", status = "good2go" }, new MyClass() { email_address = "email2@email.com", status = "good2go" } };
        var json = JsonConvert.SerializeObject(new
        {
            operations = data
        });

using System.Web.Script.Serialization;
var jsonSerialiser = new JavaScriptSerializer();
var json = jsonSerialiser.Serialize(data);