Synthesis, Table of Contents PAPER © Georg Thieme Verlag Stuttgart · New York Synthesis of Near-Infrared Absorbing Bisquarylium Dyes Bearing Unsymmetrically Extended π-Conjugation Structures Shigeyuki Yagi*, Kazuhisa Nakai, Yutaka Hyodo, Hiroyuki Nakazumi*Department of Applied Materials Science, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, JapanFax: +81(72)2549913; e-Mail: yagi@ams.osakafu-u.ac.jp; Recommend Article Abstract Buy Article All articles of this category Abstract Novel cationic bisquarylium dyes 3 and 4 were prepared by the reaction of benzothiazolinosquarylium dye 2 with a series of 4-substituted 3-hydroxy or 3-ethoxycyclobut-3-ene-1,2-diones. These dyes exhibit large and intense absorptions in the near-infrared region with varying absorption maxima in the range of 771 to 815 nm. Key words: squarylium dyes - X-ray crystallographic analysis - heterocycles - π-conjugation structures - chromophores Full Text References References 1 Sprenger H.-E. Ziegenbein W. Angew. Chem., Int. Ed. Engl. 1968, 7: 530 2a Tam AC. Appl. Phys. Lett. 1980, 37: 978 2b Law KY. Bailey FC. J. Imaging Sci. 1987, 31: 172 3a Matsuoka M. In Absorption Spectra of Dyes for Diode Lasers Bunshin; Tokyo: 1990. p.51 3b Fabian J. Nakazumi H. Matsuoka M. Chem. Rev. 1992, 92: 1197 4a Merritt VY. Hovel HJ. Appl. Phys. Lett. 1976, 29: 414 4b Loutfy RO. Hsiao CK. Kazmaier PM. Photogr. Sci. Eng. 1983, 27: 5 5a Thomas KG. Thomas KJ. Das S. George MV. Chem. Commun. 1997, 597 5b Kukrer B. Akkaya EU. Tetrahedron Lett. 1999, 40: 9125 5c Dilek G. Akkaya EU. Tetrahedron Lett. 2000, 41: 3721 6a Trebs A. Jacob K. Angew. Chem., Int. Ed. Engl. 1965, 4: 694 6b Maahs G. Hegenberg P. Angew. Chem., Int. Ed. Engl. 1966, 5: 888 7 Law KY. Bailey FC. J. Org. Chem. 1992, 57: 3278 8 Terpetschnig E. Lakowicz JR. Dyes and Pigments 1993, 21: 227 9 Yagi S. Hyodo Y. Matsumoto S. Takahashi N. Kono H. Nakazumi H. J. Chem. Soc., Perkin Trans. 1 2000, 599 10 Nakazumi H. Natsukawa K. Nakai K. Isagawa K. Angew. Chem., Int. Ed. Engl. 1994, 33: 1001 11 Hyodo Y. Nakazumi H. Yagi S. Nakai K. J. Chem. Soc., Perkin Trans. 1 2001, 2823