An efficient green synthesis and antibacterial activity of 1,3-benzoxazine and 1,3-naphthoxazine using NaCl.SiO2 as solid catalyst in neat condition

A series of 1,3-oxazine derivatives were synthesized by a one-pot three-component (ie, phenol, formaldehyde, amine) method where SiO₂ bonded with NaCl was used as a reusable, more efficient, easily prepared, and available solid catalyst. The reactions were also carried out at room temperature for greener approach. in vitro studies for the synthesized compounds were also done against two gram-positive (Bacillus subtilis and Staphylococcus aureus) and two gram-negative bacteria (Escherichia coli and Klebsiella pneumonia) to check for their applicability as an antibacterial agent where some of the synthesized compounds gives the best antibacterial activity against selected bacterial strains. Streptomycin was used as a standard control for all the microbial test.     

A computational approach to understanding the mechanism of aromatic bromination using quaternary ammonium tribromides

Quaternary ammonium tribromides (QATBs) have garnered interest for nearly a century now. Various types of tribromides have been synthesized over the years and their diverse applications have been extensively reported. However, despite the fact that these reagents are touted as safer alternatives to the very poisonous bromine, there is insufficient information on the structure of Br₃^? in QATB systems and there is still no clear explanation for how the tribromide ion (Br₃^?) participates in bromination reactions. This paper reports a through structural assessment of Br₃^?, followed by an attempt was made to fully understand the mechanistic behaviour of tribromide during bromination of aromatic compounds.