Synthesis, Spectral and Electrochemical Properties, and Theoretical Studies of Highly Functionalized Fused Triazole-Isoindoline Derivatives as a Donor-Acceptor System

Abstract

Triazole and propargyl group functionalities are frequently utilized in the construction of efficient blue-emitting materials, serving as acceptors and donors, respectively. Leveraging the synergistic effect of donor-acceptor coupling between these moieties, three new compounds, namely CB-But-I2, Ph-But-I2, and DP-But-I2, were synthesized. Given the advantageous strategy of combining electron donors and acceptors to optimize carrier injection and transport, CB-But-I2, Ph-But-I2, and DP-But-I2 demonstrate remarkable capabilities in both hole and electron transportation. A metal-free synthesis approach was employed to produce highly functionalized 1,2,3-triazole cores incorporating electronic donor and acceptor functionalities. This synthesis method involved the “Click reaction” ring formation between acetylene and azide compounds of 2-(4-bromobutyl) isoindoline-1,3-dione, catalyzed by copper sulfate pentahydrate and assisted by ascorbic acid as a base. The process boasts several advantages, including mild reaction conditions, accessibility of precursors, metal-free synthesis, straightforward setup, and the generation of various substituted regioselective triazole compounds in satisfactory yields. All synthesized compounds were found to possess thermal stability and exhibited fluorescence within the 292–355 nm range. Moreover, a significant positive solvato-chromic behavior was noted across different solvents with varying polarities, and the theoretical values were compared against experimental data for validation.