How to create reference list with maths in title on Mendeley for Latex
Mendeley defaults seem to be to automatically escape LaTeX special characters, which can mean math mode text gets mangled. In my version (1.19.4), this can be changed by going: Mendeley Desktop -&gt; Preferences -&gt; BibTeX and unchecking Escape LaTeX special characters (#{}%&amp; etc.)
Edit: once you've done that you can include math mode markup in your titles, as suggested by @Federico Poloni, e.g. {$2^2$}, and it will not be mangled by Mendeley.
This will mean that all special characters will not be escaped, so you'll have to do it by hand otherwise your compile will likely throw errors. For instance titles including &amp; will need to escaped manually (e.g. \&amp;) in Mendeley.