Supramolecular complex catalyzed green synthesis of 9-(2-Ethylhexyl) carbazole: Structural, optical and DFT investigations

Abstract

Green chemical principles such as (a) bio-renewable solvent utilization, (b) phase transfer catalysis (c) coloumn chromatography free methodologies, and (d) mild reaction conditions (i.e., room temperature, open atmosphere enough to carry out alkylation of carbazole) were optimized during the synthesis of 9-(2-Ethylhexyl) carbazole. High yield of title compound (96 %) was achieved with 1.0 equivalents of base NaOH and catalytic amount (0.1 equivalents) of 18C6 using a combination of 2-MeTHF and water green solvents. Structure of the Carbazole, 9-(2-Ethylhexyl)carbazole was conformed by analyzing the spectral data such as NMR, IR and Mass. DFT studies were explored to analyze various energy components and reactivity descriptors of the title product. The energy gap in between HOMO and LUMO of the this compound is found to be -4.59ev. Further, UV–Visible spectral analysis has been carried out in various solvents in different molarities to understand the stability of the compound with respect to various wavelength points. The increment of dielectric constant of the solvent (from 1,4 Dioxane to Acetonitrile in upward direction) also indicates major blue side shift. These studies are expected to offer critical insight into the correlation between structural, optical parameters.