Research Letters in Physical Chemistry 
Volume 2008 (2008), Article ID 314898, 4 pages
doi:10.1155/2008/314898
Research Letter

The Effect of Tb and Sm Ions on the Photochromic Behavior of Two Spiropyrans of Benzoxazine Series in Solution

Esam Bakeir,1 G. M. Attia,1 Maria Lukyanova,2 Boris Lukyanov,2 and M. S. A. Abdel-Mottaleb1

 1Nanophotochemistry Lab, Department of Chemistry, Faculty of Science, Ain Shams University, Abbassia, Cairo 11566, Egypt
2Department of Chemistry, Institute of Physical and Organic Chemistry, Southern Federal University, Rostov-on-Don 344006, Russia
Received 18 November 2007; Accepted 17 January 2008

Recommended by Bern Kohler

Abstract

The photochromism of [7′-hydroxy-8′-formyl-3-methyl-4-oxospiro[1,3-benzoxazin-2,2′-[2H-1]benzopyran],SP(I),[7′-hydroxy-8′-formyl-3-benzyl-4-oxospiro[1,3-benzoxazin-2,2′-[2H-1]benzopyran] SP(II) and their coordination with Tb3+and Sm3+ ions have been studied in DMF. UV/vis induced-color development due to heterolytic bond cleavage of SP(I) and SP(II) is greatly influenced by complexation with the lanthanide ions. The irradiation-induced color enhancement due to ring opening and thermal decoloration of the open forms of SP(I), SP(II) follows first-order kinetics. Physical characteristics of the studied systems such as colorability and relaxation time of thermal bleaching parameters were determined. Moreover, light-energy transfer-induced luminescence of lanthanide ions via coordination with the two spirobenzoxazines was monitored.