There aren't any.
Can you cite any court case where an illegal alien was denied 4th Amendment protections during an arrest and the court specified the police were not obligated to abide by the 4th Amendment when arresting illegal aliens?
There are a number of cases that hold that the Border Patrol has a greater latitude in conducting searches for illegal aliens near the border, but they are still couched in a lot of boilerplate language about "reasonableness," etc. And an extended detention of a suspected illegal alien as a result of these searches triggers the Terry Rule and the 4th Amendment.