How do you escape quotes within a Union Query?

[mda]

I am using IIF(criteria, true, false) in a SQL query in Access. It works when I run it as its own query.
I need to use this IIF function within a Union query - meaning, I need to have something like:
UNION (SELECT IIF(FieldName = “Field Value”, “Value1”, “Value2”)
However, whenever I start include quotes in a union query, the query no longer works. I have tried double and single quotes, I've tried escaping the quotes and I'm at a loss for what to do next.
Any suggestions, or is this by design? I have resorted to putting the SQL queries into a VBA function and then calling the VBA function from within the union query, but that is getting messy.
Thanks!

[CJ_London]

The syntax of the bit of code you provided is not valid, but I can't suggest an alternative because I can't see the context of what you are trying to do. Suggest you explain in more detail the issue you are trying to overcome. Provide some sample data and the required outcome.

I can say that with a union query you cannot change a field name dynamically, to do this you would need to build and run the query via vba.