Boron functionalization of BODIPY by various alcohols and phenols

Abstract

The synthesis of new B-O BODIPY derivatives functionalized with different alkoxy or diarylalkoxy derivatives is described. These compounds were synthesized from the reaction of different B-F BODIPY precursors with various alcohols and phenols, in the presence of AlCl3. Water-soluble dyes could be synthesized as well with this method, specifically by the introduction of polyethyleneglycol (PEG) groups. A photophysical study of the different compounds was performed, and showed that the B-O BODIPY derivatives exhibit rich fluorescence properties. Finally, the conjugation of the BODIPY core has been extended using two distyryl groups, hence providing NIR emitting BODIPY derivatives, in which one or two PEG groups have been anchored, making these systems very promising for future medical imaging applications.

Near‐IR BODIPY Dyes à la Carte—Programmed Orthogonal Functionalization of Rationally Designed Building Blocks

“…Replacement of the Fa toms by alkoxy,p henoxy, [31] alkynyl, [32] aryl, [33] heteroaryl, [34] Cl, [35] and carboxylatem oieties, [36] has been reported. However,t hese transformations, thoughi nteresting, lie beyondt he scope of the present paper.…”

Synthesis of 4,4′-functionalized BODIPYs from dipyrrins

“…These reactions require strong nucleophilic agents, such as Grignard or organolithium reagents, [4][5][6][7][8][9][10][11][12] and alkoxides, 13,14 or alternatively, can be accomplished under milder reactions in the presence of a Lewis acid (usually AlCl 3 or BF 3 •OEt 2 ). [15][16][17][18][19][20][21] These methodologies afford either the 4-mono-or 4,4'-disubstituted BODIPYs via careful control of the reaction conditions, and additional synthetic steps are required for the preparation of 4,4'-difunctionalized BODIPYs bearing two different substitutents at the boron center. Alternatively, mono-and disubstituted BODIPYs can be prepared by reaction of dipyrrins with haloboranes.…”

“…TMSCN has been previously employed for substitution of the fluorides in a BF 2 -BODIPY, although the reaction proceeds only in the presence of a Lewis acid, such as tin tetrachloride or boron trifluoride. 9 Under these milder reaction conditions, nucleophiles functionalized with amine, ester and acetylene functionalities can be used, allowing for further derivatization or conjugation of the BODIPY, 9,20,21 as well as the introduction of a polyethylene glycol group for increased solubility.…”

BODIPY-conjugated chitosan nanoparticles as a fluorescent probe

“…Therefore, we have concluded that the tripolyphosphoric groups of TPP are linked with ammonium groups of chitosan to form nanoparticles. Carboxylated BODIPY was synthesized and purified successfully using the method previously described with some modifications (Brizet et al, 2013). The BODIPY-COOH compound was characterized by classical spectroscopic analysis such as NMR spectroscopy and the final product was obtained in 38% yield.…”

“…4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY-COOH) was synthesized by the method of Brizet et al (2013) with some modification. In the procedure, to an anhydrous dichloromethane (DCM) (50 mL) of 2,4-dimethylethylpyrrole (DMAP) (739.2 mg, 6.0 mmol), 4-carboxy-benzaldehyde (450.4 mg, 3.0 mmol) and catalytic amount of trifluoroacetic acid (2-3 drops) were added.…”