The Mexican has netted 22 times in 44 appearances for Nuno Espirito Santo's side this campaign.
United and Real Madrid are both in the market for a new striker this summer and have been keeping tabs on Jimenez.
"For me, Wolverhampton are too small, the best option for Raul is to continue progressing; he can only aspire to the Europa League," Zamorano told Medio Tiempo.
"He has to think about playing the Champions League, being a world class striker, empowering himself at a professional level and playing for a team like Real Madrid."
"Today, if I were Raul, I wouldn't think twice. Karim Benzema is a great player, but Jimenez has nothing to envy him; what's more, Manchester United don't have a nine, there he is, he knows the league and the team needs a number nine."