BODIPY-Based Photoacid Generators for Light-Induced Cationic Polymerization

Abstract

Photoacid generators (PAGs) are organic compounds that can generate protons (H+) upon irradiation with certain wavelengths of light. In this work, we designed and synthesized the first BODIPY-based PAGs with D–A and D−π–A conjugation structures and achieved green and red LED light-induced acid generation. By the use of red-light absorbance, red-LED-triggered cationic polymerization was demonstrated as a proof-of-concept application of these PAGs.

A BODIPY‐Based Far‐Red‐Absorbing Fluorescent Probe for Hypochlorous Acid Imaging

“…The targeted HClO probe ( BD‐NOH ) was synthesized via a three‐step reaction sequence (Scheme 1) from the BODIPY core structure [51] . To achieve far‐red absorbability, in the first step the BODIPY core was conjugated with diphenyl sulfide aldehyde using a microwave reactor to offer a 41 % yield of compound 1 .…”

“…The targeted HClO probe (BD-NOH) was synthesized via a three-step reaction sequence (Scheme 1) from the BODIPY core structure. [51] To achieve far-red absorbability, in the first step the BODIPY core was conjugated with diphenyl sulfide aldehyde using a microwave reactor to offer a 41 % yield of compound 1. After conjugation, compound 1 exhibited an extended maximum absorption wavelength close to 650 nm, partially benefiting from the electron-donating groups of diphenyl sulfide.…”

Activating Acid‐Sensing Ion Channels with Photoacid Generators

“…Chemists have developed various photochemical tools to control ion channels, [12] including caged compounds, and photoswitches [13] . Photoacid generators (PAGs) are ionic or nonionic compounds that release H + upon light irradiation, and have seen widespread application in lithography and cationic polymerization [14,15] . For biological applications, tailor‐made PAGs were used to induce pH imbalances in the cytosol of cancer cells for therapeutic treatment [16] .…”

“…[13] Photoacid generators (PAGs) are ionic or nonionic compounds that release H + upon light irradiation, and have seen widespread application in lithography and cationic polymerization. [14,15] For biological applications, tailormade PAGs were used to induce pH imbalances in the cytosol of cancer cells for therapeutic treatment. [16] Herein, a sulfoniumbased PAG (PAG-1) [17] with low dark cytotoxicity was selected for this study to verify our hypothesis that PAGs may be feasible to photoactivate ASICs (Scheme 1).…”

Regulating Mitochondrial pH with Light and Implications for Chemoresistance

“…[12] Lipophilic cationic properties of triphenyl sulfonium salts are structurally similar to triphenyl phosphonium (TPP) salts (a frequently used mitochondria targeting moiety), and make them promising candidates for mitochondriat argeting. [13] Herein, we used av isible light absorbing BODIPY chromophore-basedt riarylsulfonium PAG( BD-PAG) ( Figure 1) [14] to targetm itochondria.A fter absorbing the energy of red photons, BD-PAG is promoted to an electronically excited state that facilitates cleavage of the CÀS bond,f orming ac ation-radical on the sulfur-containing fragment,a nd generatesH + after hydrogen atom abstraction. [15] Herein, we provide the first report of using PAGs to regulate pH mito for the purposeo fd epolarizing the mitochondrial membrane and attenuatingd rug resistance in chemotherapy treatment.…”