YES, a condo association can reject a buyer if the bylaws give them the power (read the article link below). It requires a 2/3 vote of the owners. But I have not run up against one in NYC. Otherwise Mitchell is correct in the Board has a Right of First Refusal which is rarely exercised.
In NYC condos have the right of first refusal. They can reject a buyer by not issuing a waiver of first right of refusal. They must buy the condo for the same price as the potential buyer. It is rare but can happen.
Technically, no. Condo boards have the "right of first refusal" which means that they have the option to buy the apartment for the same price the buyer offered. It's safe to say that this rarely if ever happens.