Synthesis 2002(3): 0413-0417
DOI: 10.1055/s-2002-20034
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, Japan
Fax: +81(72)2549913; e-Mail: yagi@ams.osakafu-u.ac.jp;
Further Information

Publication History

Received 26 October 2001
Publication Date:
28 July 2004 (online)

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.