My supervisor is trying to get me fired because I don't agree with his unethcial ideas. Do I have grounds to sue the company if I'm fired?

1) I felt uncomfortable before he was promoted to my supervisor as he would practice immoral conversation with my office mate in front of me. 2) When he became the supervisor of my department, he asked me to 'take notes' on everyone in the department & I declined. 3) He asked me to do undertake procedures which was something higher management would do and I said yes so I could help our department out. He said he would help when I had questions. 4) When I needed advice, he never committed to it and I gave this email to the HR department. 5) I allowed him to get under my skin and I overstepped my boundaries. He has a reason to fire me now. Do I quit? If they fire me, do I have grounds to sue the employer because they did not help me when I asked? 6) I know that my employer has taken his side and refuses to see mine or the others. I understand they are a big system and they have lawyers themselves. I need some legal advice before they would probably fire me next week. Thank you.