HTML input pattern to match literally word in curly brackets like {name}

I want to make sure that a text input field includes somewhere in the string {name} literally, before submitting the form. For example it should match 123{name}456

I try the regex pattern {name}+ in regex101.com and other similar testers and it works as expected.

However, I learned that I should escape the brackets and after a lot of struggle I found how to match exactly {name} - with pattern = "\\{name\\}" But when I try to make it match when there are other characters around, it just doesn't work. I tried "\\{name\\}+" and "(\\{name\\})+" and don't get what's wrong.

Please help, it's been an hour already...