Browsing by Author "Manjit Singh"

Now showing 1 - 3 of 3

Green and efficient iron-catalyzed cross-dehydrogenative coupling for the synthesis of α,β-unsaturated ketones via C(sp3)-H functionalization
(Royal Society of Chemistry, 2025) Manjit Singh; Poonam Rajesh Prasad
An efficient C-C cross-coupling approach for the synthesis of α,β-unsaturated ketones was developed through C(sp3)-H functionalization of acetophenone and methylarene under thermal conditions in the presence of a green catalyst, FeCl3·6H2O, with DMF as a solvent and atmospheric O2 (air) as an oxidant. The method was useful for a wide range of substrates, indicating good functional group compatibility and providing an innovative approach to forming new C-C bonds from inexpensive, readily available starting materials. Thus, the main advantages of the present methods are one-pot reactions, environmentally friendly approaches, cost-effectiveness, broad substrate scope, short reaction times, easy workup procedures, and good yields. © 2025 The Royal Society of Chemistry.
Liquid-assisted grinding (LAG) approach, metal-free synthesis of 2,3-dihydro-1,5-benzothiazepines and their electrochemical properties
(CSIRO, 2024) Manjit Singh; Kuldeep Kumar Maurya; Manisha Malviya
In this work, we have disclosed a facile metal-free synthesis of pharmaceutically fascinating and biologically important benzothiazepines in the presence of a few drops of ethanol. The present methodology converts chalcones and ortho-amino thiophenol into 2,3-dihydro-1,5-benzothiazepines under ambient conditions using liquid-assisted grinding, resulting in rapid synthesis in a very short period. This process is eco-friendly, operationally simple and gives good to excellent yields of products with easy isolation. This approach offers a facile synthesis of 2,3-dihydro-1,5-benzothiazepines from three readily available starting materials. An electrochemical study of the benzothiazepine derivatives was undertaken using cyclic voltammetry and electrochemical impedance spectroscopy techniques. © 2024 CSIRO. All rights reserved.
Synthesis of imidazole-fused nitrogen-bridgehead heterocycles catalysed by lipase and their antifungal and antimicrobial bioactivity
(Royal Society of Chemistry, 2024) Manjit Singh; Manisha Malviya; Vijay B. Yadav; Aishwarya Nikhil; Munesh Gupta
An effective approach for selective C-N bond formation for synthesising imidazo[1,2-a] pyridine-based heterocycles using porcine pancreatic lipase (PPL) as a biocatalyst has been devised. Under moderate conditions, a series of imidazo[1,2-a]pyridine-based heterocycle derivatives were synthesised with remarkable selectivity in good-to-excellent yields (89-95%). Further, the antimicrobial and antifungal activities of derivatives 3ha, 3ka, 3fa, 3hc, and 3eb were observed, and they were found to be biologically active in antimicrobial susceptibility tests for Gram-positive bacteria (Enterococcus faecalis ATCC 29212 and Staphylococcus auris ATCC 25923), Gram-negative bacteria (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853) and fungal strains (Candida albicans ATCC 90028 and Candida tropicalis ATCC 750). © 2024 The Royal Society of Chemistry.