Multifunctional Porous Organic Polymers: Tuning of Porosity, CO₂, and H₂ Storage and Visible-Light-Driven Photocatalysis

A series of porous organic polymers (POPs) were fabricated based on a boron dipyrromethene (BODIPY) core. The variation of the substituents in the BODIPY core and the fine-tuning of the Sonogashira polycondenzation reaction with 1,3,5-triethynylbenzene led to the formation of POPs with a wide range of surface area and porosity. A 10-fold increase in surface area from 73 m² g^–1 in <b>BDT1a</b> polymer to 1010 m² g^–1 in <b>BDT3</b> was obtained. Simultaneously, the porosity was changed from mesoporous to ultramicroporous. The surface area of <b>BDT3</b> turned out to be the highest reported so far for BODIPY-based POPs. Molecular dynamics simulation coupled with Grand Canonical Monte Carlo simulations revealed the effect of substituents alkyl groups and rigidity of the core structures on the surface properties of the POPs. Detailed gas adsorption studies of the polymers revealed a high uptake of CO₂ and H₂. The highest uptake capacity of 16.5 wt % for CO₂ at 273 K and 2.2 wt % for H₂ at 77 K was observed for <b>BDT3</b> at 1 bar pressure. The isosteric heat of adsorption (<i>Q</i>_st) of <b>BDT3</b> for CO₂ was found to be as high as 30.6 kJ mol^–1. Electron paramagnetic resonance studies revealed the generation of singlet oxygen upon photoexcitation of these polymers. The BODIPY-based POPs turned out to be excellent catalysts for visible-light-driven photo-oxidation of thioanisole. The present study establishes BODIPY-based POPs as a new class of multifunctional materials

Copper/Zinc-Catalyzed Stitching of 2‑Carbonylanilines with Bis(ynamides): Access to Pyrrolo[2,3‑<i>b</i>]quinolines and Its Photophysical Studies

Herein, a one-pot desulfonylative protocol enabled by copper(II)/zinc(II) salts to access pyrrolo[2,3-b]quinolines in good to excellent yields from 2-carbonylanilines and ynamide-derived buta-1,3-diynes has been reported. Significantly, various 2-carbonylanilines carrying reactive functional groups are well tolerated. Moreover, a gram-scale synthesis and synthetic application highlight the practical utility of the current protocol. Notably, the fluorescence properties of pyrrolo[2,3-b]quinolines have been recorded, and their potential use as a fluorescent probe in the imaging of live cells has been demonstrated

Copper/Zinc-Catalyzed Stitching of 2‑Carbonylanilines with Bis(ynamides): Access to Pyrrolo[2,3‑<i>b</i>]quinolines and Its Photophysical Studies

Herein, a one-pot desulfonylative protocol enabled by copper(II)/zinc(II) salts to access pyrrolo[2,3-b]quinolines in good to excellent yields from 2-carbonylanilines and ynamide-derived buta-1,3-diynes has been reported. Significantly, various 2-carbonylanilines carrying reactive functional groups are well tolerated. Moreover, a gram-scale synthesis and synthetic application highlight the practical utility of the current protocol. Notably, the fluorescence properties of pyrrolo[2,3-b]quinolines have been recorded, and their potential use as a fluorescent probe in the imaging of live cells has been demonstrated

Unraveling Molecular Assembly and Tracking Lipid Droplet Dynamics Using Fluorescent Phenanthroimidazole Derivatives

Small strategic perturbations of the molecular structures impart significant variation in the evolution dynamics and properties of supramolecular self-assembled architectures. However, probing the in situ evolution dynamics of molecular assembly remains a challenge. Herein, we unraveled the real-time, early stage environment-sensitive dynamic molecular self-assembly processes and stimuli-induced reversible morphological transformation between supramolecular fibers and spherical nanoaggregates of alkyl chain-substituted phenanthroimidazole-based luminogen (BPIB1) through fluorescence lifetime imaging microscopy (FLIM). The presence of an octyl chain and basic nitrogen centers in BPIB1 led to a distinct self-assembly pattern. The gradual progression in the fluorescence lifetime provides a unique strategy for elucidating the dynamics of the self-assembly process leading to distinct nano/microarchitectures. Among the varied self-assembled structures, the smaller-sized (diameter ∼ 20–30 nm), highly photostable, water-dispersible, and biocompatible fluorescent nanoaggregates of BPIB1 were employed for tracking the dynamics of lipid droplets in live cells and a model organism, C. elegans, using fluorescence correlation spectroscopy and FLIM. Thus, a combined microscopic and spectroscopic approach demonstrated in the present study opens up new avenues to explore the formation pathways of diverse molecular aggregates and their use to decipher complex organelle dynamics

Unraveling Molecular Assembly and Tracking Lipid Droplet Dynamics Using Fluorescent Phenanthroimidazole Derivatives

Small strategic perturbations of the molecular structures impart significant variation in the evolution dynamics and properties of supramolecular self-assembled architectures. However, probing the in situ evolution dynamics of molecular assembly remains a challenge. Herein, we unraveled the real-time, early stage environment-sensitive dynamic molecular self-assembly processes and stimuli-induced reversible morphological transformation between supramolecular fibers and spherical nanoaggregates of alkyl chain-substituted phenanthroimidazole-based luminogen (BPIB1) through fluorescence lifetime imaging microscopy (FLIM). The presence of an octyl chain and basic nitrogen centers in BPIB1 led to a distinct self-assembly pattern. The gradual progression in the fluorescence lifetime provides a unique strategy for elucidating the dynamics of the self-assembly process leading to distinct nano/microarchitectures. Among the varied self-assembled structures, the smaller-sized (diameter ∼ 20–30 nm), highly photostable, water-dispersible, and biocompatible fluorescent nanoaggregates of BPIB1 were employed for tracking the dynamics of lipid droplets in live cells and a model organism, C. elegans, using fluorescence correlation spectroscopy and FLIM. Thus, a combined microscopic and spectroscopic approach demonstrated in the present study opens up new avenues to explore the formation pathways of diverse molecular aggregates and their use to decipher complex organelle dynamics

Unraveling Molecular Assembly and Tracking Lipid Droplet Dynamics Using Fluorescent Phenanthroimidazole Derivatives

Small strategic perturbations of the molecular structures impart significant variation in the evolution dynamics and properties of supramolecular self-assembled architectures. However, probing the in situ evolution dynamics of molecular assembly remains a challenge. Herein, we unraveled the real-time, early stage environment-sensitive dynamic molecular self-assembly processes and stimuli-induced reversible morphological transformation between supramolecular fibers and spherical nanoaggregates of alkyl chain-substituted phenanthroimidazole-based luminogen (BPIB1) through fluorescence lifetime imaging microscopy (FLIM). The presence of an octyl chain and basic nitrogen centers in BPIB1 led to a distinct self-assembly pattern. The gradual progression in the fluorescence lifetime provides a unique strategy for elucidating the dynamics of the self-assembly process leading to distinct nano/microarchitectures. Among the varied self-assembled structures, the smaller-sized (diameter ∼ 20–30 nm), highly photostable, water-dispersible, and biocompatible fluorescent nanoaggregates of BPIB1 were employed for tracking the dynamics of lipid droplets in live cells and a model organism, C. elegans, using fluorescence correlation spectroscopy and FLIM. Thus, a combined microscopic and spectroscopic approach demonstrated in the present study opens up new avenues to explore the formation pathways of diverse molecular aggregates and their use to decipher complex organelle dynamics