1. Institute of Chemistry, Organic Chemistry; Martin Luther University Halle-Wittenberg; Kurt-Mothes Str. 2 06120 Halle/Saale Germany
2. Department of Chemistry; Faculty of Science; Cairo University; Giza Egypt
3. Institute for Experimental Physics; Otto-von-Guericke University Magdeburg; Universitätsplatz 2 39106 Magdeburg Germany