Reach Beijing airport at 11.30pm. What are the transport i can take to Dongzhimen station

As you are arriving at 11:30 pm, I suggest you take airport shuttle bus line 2 to reach Dongzhimen directly.

To reach your hotel near Wangfujing that late, I also suggest you take the shuttle bus line 2 and you need to get off at the local Railway Station, where you can take a taxi to reach your hotel in about 10min.