title: Novel stilbene-triazine symmetrical optical brighteners: synthesis and applications.
abstract: A series of new high light fastness, hot pressing fastness optical brighteners was efficiently synthesized by a three-step approach involving the successive replacement of the three chloro groups of 2,4,6-trichloro-1,3,5-triazine under different conditions of temperature and pH. Thus, 2,4,6-trichloro-1,3,5-triazine was treated with different anilines and the resulting dichlorotriazinyl intermediates (3a-I) were further condensed with 4,4-diaminostilbene-2,2'-disulfonic acid to afford bis-monochlorotriazine (5a-I) followed by nucleophilic substitution with ethanolamine to furnish the final hybrid brighteners (7a-I). All of the newly synthesized compounds were characterized by Fourier-Transform Infrared (FT-IR), UV-visible absorption, NMR spectroscopy and the elemental analyses. The synthesized optical brighteners were also assessed for their efficacy as fluorescent brightening agents.
authors.affiliation: Department of Chemistry, Quaid-I-Azam University, Islamabad, 45320, Pakistan, asaeed@qau.edu.pk.
authors.forename: Aamer
authors.initials: A
authors.lastname: Saeed
authors.forename: Ghulam
authors.initials: G
authors.lastname: Shabir
authors.forename: Iram
authors.initials: I
authors.lastname: Batool