Installing a package that is in a different target .NET environment

I currently have a .NET 4.5 project, Project "X". I want to install a package that targets (written on top of) .Net 4.5.2, Project "Y".

Is there a way where I don't need to upgrade Project-X to 4.5.2 and still install Project-Y? The reason I don't want to update X is because I have several other projects in a solution that targets it and would not prefer not to update my entire solution to 4.5.2.