You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(5-fluoro-1'-prop-2-enylspiro[2H-indole-3,4'-piperidine]-1-yl)-[3-(trifluoromethoxy)phenyl]methanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C23H22F4N2O2
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