A quantum chemical study: thoughtful exploration for optimal donors in Y-type dual donor-based dye sensitizers.

This research explores the influence of different dual donors on the effectiveness of dye sensitizers. We selected 35 diverse donors to construct Y-type dual donor-based dyes, connecting them with thiophene as the π-spacer and cyanoacrylic acid as the acceptor. Density functional theory calculations indicate that these dual donor-based dyes exhibit superior optoelectronic properties compared to their single donor counterparts. Notably, significant variations in charge distribution among the different dual donors affect their donor capabilities. Our calculations specifically highlight the enhanced thermodynamic parameters, including light harvesting efficiency (LHE), the free energy of dye injection (ΔGinject), and regeneration (ΔGreg), for donor moieties containing nitrogen atoms, such as NS-3 (N,N-dimethylaniline), NS-5 (diphenylamine), NS-6 (triphenylamine), and NS-8 (4-methoxy-N-(4-methoxyphenyl)-N-phenylaniline). These results suggest that nitrogen-containing donor moieties act as promising candidates for donors for efficient dye sensitizers. However, further experimental validation in the near future will be necessary to confirm our findings.

Catalytic and Mechanistic Approach to the Metal-Free N-Alkylation of 2-Aminopyridines with Diketones.

N-alkylation of amines is an important catalytic reaction in synthetic chemistry. Herein, we report a simple strategy for the N-alkylation of 2-aminopyridines with 1,2-diketones using BF3·OEt2 as a catalyst. The reaction proceeds under aerobic conditions, leading to the formation of a diverse range of substituted secondary amines in good to excellent yields. A close inspection of the mechanistic pathway using various spectroscopic techniques and the computational study revealed that the reaction proceeds through the formation of an iminium-keto intermediate with the liberation of CO2.

Evaluation of the status of marine plastic pollution along a tourist beach of Bay of Bengal during lockdown and post lockdown.

Marine plastic pollution is a global issue that has calamitous consequences for global economy, biodiversity, human health, and the climate. A few of the studies were carried out on the Gopalpur coast and the current baseline survey was conducted during Covid-19 pandemic lockdown (April-August 2021) and post lockdown (August-September 2021).The survey was covered about 1500 m along the coast, divided into 10 equal zones of each (20 × 150 m2) to collect the plastic debris based on colour, density, and weight. Plastic debris was categorized into 33 types with an average 1.276 g/m2 during lockdown and was categorized into 34 types with an average 3.34 g/m2 in post lockdown. The results imply that tourism has a greater impact on the beach in terms of pollution when compared with the local sources, which will have a drastic effect on the aesthetics of the beach, neighbouring turtle nesting site and indirectly on human health.