Table of Contents
Research Letters in Organic Chemistry
Volume 2008 (2008), Article ID 959372, 5 pages
Research Letter

Photochromism of Dihydroindolizines Part XI: Synthesis of Novel Carbon-Rich Photochromic Dihydroindolizines-Based Potential Electronic Devices

1Chemistry Department, Faculty of Science, Assiut University, 71516 Assiut, Egypt
2Chemistry Department, Faculty of Science, Taibah University, Al-Madina Al-Munawara 30002, Saudi Arabia

Received 9 July 2008; Accepted 12 October 2008

Academic Editor: Cyril Parkanyi

Copyright © 2008 Saleh Abdel-Mgeed Ahmed. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Novel carbon-rich photochromic dihydroindolizine (DHI) derivatives substituted in the fluorene part (region A) in addition to the new spirocyclopropene 6 have been synthesized. The synthesis of dimethyl 2 , 7 -diethynylspiro[cycloprop[2]ene-1, 9 -fluorene]-2,3-dicarboxylate precursor 6 was accomplished in five steps, starting with the literature known conversion of fluorene to 2,7-dibromo-9H-fluoren-9-one in 56% yield over three steps. The chemical structures of the new synthesized materials have been elucidated by both analytical and spectroscopic tools. Three alterative synthetic pathways for the synthesis of DHI 9 have been established.