Furo[3,2-c]coumarin-derived Fe3+ Selective Fluorescence Sensor: Synthesis, Fluorescence Study and Application to Water Analysis

Abstract

Furocoumarin (furo[3,2-c]coumarin) derivatives have been synthesized from single step, high yielding (82-92%) chemistry involving a 4-hydroxycoumarin 4 + 1 cycloaddition reaction. They are characterized by FTIR, 1 H-NMR, and, for the first time, a comprehensive UV-Vis and fluorescence spectroscopy study has been carried out to determine if these compounds can serve as useful sensors. Based on the fluorescence data, the most promising furocoumarin derivative (2-(cyclohexylamino)-3-phenyl-4Hfuro[3,2-c]chromen-4-one, FH), exhibits strong fluorescence (ФF = 0.48) with long fluorescence lifetime (5.6 ns) and large Stokes' shift, suggesting FH could be used as a novel fluorescent chemosensor. FH exhibits a highly selective, sensitive and instant turn-off fluorescence response to Fe 3+ over other metal ions which was attributed to a charge transfer mechanism. Selectivity was demonstrated against 13 other competing metal ions

One-Pot Synthesis of 4H-Pyrano[3,2-c]coumarin Derivatives Catalyzed by Deep Eutectic Solvent

“…21 In addition, tetrabutylammonium bromide (TBAB) can be used to catalyze the reaction of 4-hydroxycoumarin with ethyl benzylidenecyanoacetate to synthesize pyrano [3,2-c]coumarin derivatives (Scheme 1b). 22 There have been many related reports on synthetic methods for these compounds using many catalysts, such as metal catalysts (Fe, Cu, Pd), [23][24][25][26][27][28] NaBr, 29 ZnO, [30][31][32] hexamethylenetetramine, 33 and potassium phthalimide. 34 The major disadvantages of using these catalysts are unsatisfactory yields, long reaction times, complicated operations, and high cost.…”

Synthetic Routes to Coumarin(Benzopyrone)-Fused Five-Membered Aromatic Heterocycles Built on the α-Pyrone Moiety. Part 1: Five-Membered Aromatic Rings with One Heteroatom

“…On the other hand, coumarin represents an ingredient in perfumes [ 19 ], cosmetics [ 20 ], and as industrial additives [ 21 , 22 ]. Furthermore, coumarins play a pivotal role in science and technology as fluorescent sensors, mainly due to their interesting light-emissive characteristics, which are often responsive to the environment [ 23 , 24 , 25 , 26 ]. The coumarin (benzopyrane)-fused, membered aromatic heterocycles built on the α-pyrone moiety are an important scaffold.…”

Luminescent Behavior of Gels and Sols Comprised of Molecular Gelators

“…For example, Hu et al, designed an ionic, stimulus-responsive fluorescent gel using the long alkyl-chain coumarin acylhydrazone, CAh, as the LMOG ( Figure 1 ) [ 37 ]. Because of their luminescent properties, some coumarin derivatives are known to be able to act as sensors of ions [ 38 ]. Thus, 3% CAh in n-BuOH:water ( v : v , 9:1) forms a fluorescent gel that can selectively detect as low as 3.88 × 10 −8 M of sulphide ions (S 2− ) and 1.64 × 10 −8 M of cyanide ions (CN − ) ions in water by exhibiting a blue shift in its emission when excited at 340 nm.…”