The Preparation of a Fluorescent Dye: A Microscale TLC Experiment

Abstract

This paper describes an experiment that allows the instructor to introduce TLC as a technique for analyzing reaction mixtures by monitoring the formation of a fluorescent dye. The experiment also illustrates the effects of eluting solvent on elution order.

The synthesis of symmetrical and unsymmetrical alkylaminonaphthalic-1,8-N-alkylimides

“…The fluorescence of the 4‐alkylaminonaphthalic‐1,8‐ N ‐alkylimides ( 2 Scheme ) has been of great interest for several decades in connection with an array of technical, medical and electronic uses, for example in non‐destructive testing (NDT) for crack detection in metals1, 2 and ceramics, for laser activity,3, 4 as luminescent sensors and switches,5, 6 fluorescent probes for hypoxic cells in cancer studies7 and as photochemically‐activated antiviral substances 8–11…”

“…The fluorescence intensities and other spectral properties of the isomers 3a, 4a, 5c and analogues have been described25 without the full preparative details. Our experimental work on the reactions of the isomeric halogenonaphthalic anhydride is given in the present account since this much earlier synthetic work16–18 has escaped attention in later work8–11 and higher yields are obtainable in N ‐methylpyrrolidinone compared with other solvents. The full practical details of the use of the isomeric nitronaphthalic anhydrides in the synthesis of alkylaminonaphthalic‐1,8‐N‐alkylimides have recently been described 26.…”

ChemInform Abstract: The Synthesis and Fluorescence of Novel N‐Substituted‐1,8‐naphthylimides.

“…Dependent on the value of number of methylene groups, n, in the reactant, compound (14) can be obtained either directly from 4-aminonaphthalic anhydride (2) or from (1). Scheme 2 depicts the synthesis of compounds (10), (11), and (12) by reaction first at the anhydride group of 1 and then at the nitro group by nucleophilic displacement. Compounds (15) and (16) result from a similar procedure except that an amino acid intermediate is used instead of an amino alcohol.…”

“…The photochemistry and photophysics of the alkylaminonaphthalic-1,8-N-alkylimides continues to be of wide interest in technical, medical and electronic fields. In addition to their application in non-destructive testing (NDT) in metals and ceramics [1,2], laser applications [3,4], for sensors and switches [5][6][7], probes in cancer studies [8,9] and for their anti-viral activity [10][11][12][13], more recent research has highlighted their potential as electroluminescent materials [14][15][16][17] and as fluorescent sensors for metal ions [18][19][20][21][22][23][24][25][26].…”

Synthesis of a Near-Infrared Emitting Squaraine Dye in an Undergraduate Organic Laboratory

“…Although squaraines have been known since at least 1965, they have rarely been studied at the undergraduate level. Searching both the JCE Index online database and the annotated List of laboratory experiments for the keyword “squaraine” provided no prior work on the synthesis of squaraines in educational settings . This is likely due to the long reaction times reported for the synthesis of squaraines.…”