Structural properties of a series of photochromic fluorinated indolylfulgides

Mason A. Wolak, Robert C. Finn, Randy S. Rarig, Craig J. Thomas, Robert P. Hammond, Robert R. Birge, Jon Zubieta, Watson J. Lees

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Fluorinated indolylfulgides are a class of photochromic organic compounds that meet many of the requirements for use as optical memory media and optical switches. The X-ray crystal structures of a series of five photochromic fluorinated indolylfulgides have been determined, namely (3Z)-3-[1-(1,2-dimethyl-1H-indol-3-yl)-2,2,2-trifluoroethylidene]-4- (1-methylethylidene)dihydrofuran-2,5-dione (trifluoromethylisopropylideneindolylfugide), C19H16F3NO3, (I), (3Z)-3-[1-(1,2-dimethyl-1H-indol-3-yl)-2,2,3,3,3-pentafluoropropylidene]-4- (1-methylethylidene)dihydrofuran-2,5-dione (pentafluoroethylisopropylideneindolylfulgide), C20H16F5NO3, (II), (3Z)-3-[1-(1,2-dimethyl-1H-indol-3-yl)-2,2,3,3,4,4,4-heptafluorobutylidene]-4- (1-methylethylidene)dihydrofuran-2,5-dione (heptafluoropropylisopropylideneindolylfulgide), C21H16F7NO3, (III), (3Z)-3-[1-(1,2-dimethyl-1H-indol-3-yl)-2,2,2-trifluoroethylidene]-4- (tricyclo[,7]decylidene)dihydrofuran-2,5-dione (trifluoromethyladamantylideneindolylfulgide), C26H24 F3NO3, (IV), and (3Z)-3-[1-(1,2-dimethyl-1H-indol-3-yl)-2,2,3,3,4,4,4-heptafluorobutylidene]-4- (tricyclo[,7]decylidene)dihydrofuran-2,5-dione (heptafluoropropyladamantylideneindolylfulgide), C28H24F7NO3, (V). The photochromic property of fulgides is based on the photochemically allowed electrocyclic ring closure of a hexatriene system to form a cyclohexadiene. For each fulgide examined, the bond lengths within the hexatriene system alternate between short and long, as expected. Comparing the structures of the five fulgides with each other demonstrates no significant difference in bond lengths, bond angles or dihedral angles within the hexatriene systems. The distance between the bond-forming C atoms at each end of the hexatriene system does vary. Correlations of structural properties with optical properties are addressed.

Original languageEnglish (US)
Pages (from-to)o389-o393
JournalActa Crystallographica Section C: Crystal Structure Communications
Issue number7
StatePublished - Jul 2002

ASJC Scopus subject areas

  • General Biochemistry, Genetics and Molecular Biology


Dive into the research topics of 'Structural properties of a series of photochromic fluorinated indolylfulgides'. Together they form a unique fingerprint.

Cite this