Abstract: | The title compound, dimethyl 10b′‐(4‐fluorostyryl)‐8′,9′‐dimethoxy‐4‐nitro‐5′,6′‐dihydrospiro[9H‐fluorene‐9,1′(10b′H)‐pyrrolo[2,1‐a]isoquinoline]‐2′,3′‐dicarboxylate, C38H31FN2O8, is a new photochromic tetrahydroindolizine. One of the C—C bonds at the spiro C atom is very long [1.630 (2) Å], thus explaining the photochromic behaviour. |