Structural properties of a series of photochromic fluorinated indolylfulgides.
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 (trifluoromethylisopropylideneindolylfulgide), C(19)H(16)F(3)NO(3), (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), C(20)H(16)F(5)NO(3), (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), C(21)H(16)F(7)NO(3), (III), (3Z)-3-[1-(1,2-dimethyl-1H-indol-3-yl)-2,2,2-trifluoroethylidene]-4-(tricyclo[3.3.1.1(3,7)]decylidene)dihydrofuran-2,5-dione (trifluoromethyladamantylideneindolylfulgide), C(26)H(24)F(3)NO(3), (IV), and (3Z)-3-[1-(1,2-dimethyl-1H-indol-3-yl)-2,2,3,3,4,4,4-heptafluorobutylidene]-4-(tricyclo[3.3.1.1(3,7)]decylidene)dihydrofuran-2,5-dione (heptafluoropropyladamantylideneindolylfulgide), C(28)H(24)F(7)NO(3), (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.
Wolak
Mason A
MA
Department of Chemistry and W. M. Keck Center for Molecular Electronics, Syracuse University, Syracuse, NY 13244, USA.
Finn
Robert C
RC
Rarig
Randy S
RS
Thomas
Craig J
CJ
Hammond
Robert P
RP
Birge
Robert R
RR
Zubieta
Jon
J
Lees
Watson J
WJ
D000218:Adamantane / Q000737:chemistry*; D000475:Alkenes / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D017611:Fluorine Compounds / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D008027:Light; D008958:Models, Molecular; D015394:Molecular Structure; D010777:Photochemistry
D000475:Alkenes; D017611:Fluorine Compounds; D007211:Indoles; C020855:adamantylidene; C013658:propylene; D000218:Adamantane