Related Experiment Video
Updated: Jan 15, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
N-Doped π-Extended Coumarins: Synthesis and Photophysical Properties of Isoquinoline and Pyrimidine-Fused Coumarins
Rajashree Bhuyan1,2, Pranjal Gogoi1,2
1Chemical Science and Technology Division, CSIR-North East Institute of Science and Technology, Jorhat 785006, India.
Abstract:
We present here a novel series of N-doped π-extended coumarins derived from 4-aminocoumarin. Lewis and Bronsted acids mediated synthetic processes have been adopted for their synthesis, enabling the formation of C-C and C-N bonds under transition-metal-free conditions. This previously unexplored process delivers the target π-extended coumarins in good yields and provides access to isoquinoline- and pyrimidine-fused ring systems. Photophysical properties of the resulting compounds were investigated using UV-vis absorption and fluorescence emission spectroscopy. The synthesized compounds exhibit good fluorescence properties, highlighting their potential application for optoelectronic devices and as probes for bioimaging.
Related Concept Videos
Five-Membered Heterocyclic Aromatic Compounds: Overview
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
UV–Vis Spectroscopy of Conjugated Systems
One of the factors influencing λmax is the extent of conjugation in...
π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds
Structure of Conjugated Dienes
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the double...
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
