Yes, there is nothing wrong with praying them in order to enter ihraam afterwards, so that one will be entering ihraam after praying.
Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) was asked: You said that a person may enter ihraam after praying the Sunnah prayer following wudoo’ if he usually prays it. But if he does not usually do that but he offers this prayer, what is the ruling?
I think that there is nothing wrong with it. If a person does something, he does not have to do it all the time. So long as the Sunnah prayer after wudoo’ is prescribed in sharee’ah and he wants to pray, there is nothing wrong with it, and there is nothing wrong with it even if he usually does not offer this prayer. End quote.
Majmoo’ Fataawa Ibn ‘Uthaymeen (22/14).