Facile Synthesis of the Shape‐Persistent 4‐Hydroxybenzaldehyde Based Macrocycles and Exploration of their Key Electronic Properties: An Experimental and DFT Approach

Abstract

In the current study, a series of stabilized bis-acetylene incorporated 4-hydroxybenzaldehyde based macrocycles using the alkyne-homocoupling approach were synthesized in moderate yields. A total of six newly stiff macrocycles were synthesized in a stepwise manner starting from 4-hydroxybenzaldehyde. In the first step, base mediated propargylation was performed followed by copper mediated terminal alkyne homocoupling. The alkyne homocoupled substrate having carbonyl at both the terminals is cyclized in the final step via double imine formation reactions using substituted diamines as linker. All the newly synthesized rigid framework of the macrocycles were optimized at B3LYP/6-31G (d,p) level of theory. Nonlinear optical behaviors of the synthesized macrocycles were explored by the DFT calculations where high values of first-order hyperpolarizability and dipole moment were examined. In the reported study, a good agreement between experimental and theoretical parameters was observed that may play a significant contribution for the NLO applications.

Synthesis of hydrazone-based polyhydroquinoline derivatives – antibacterial activities, α-glucosidase inhibitory capability, and DFT study

“…All the heteroatoms of investigated compounds possessed a negative Mulliken atomic charge, except N(54), of compound 7 which bore a positive charge of +0.085. 31 …”

“…The chemical shifts have been calculated at the CAM-B3LYP/631-G (d,p) level of theory; this was done in the solvent dimethylsulfoxide (DMSO) and the gas phase using the SMD model. The δ 31 was computed with the help of eqn (1) , and results are given in Table S2. † δ = σ TMS – σ cal …”

“…The optimized structures of each moiety were further utilized to gain insight into the frontier molecular orbitals (FMOs), density of state (DOS), natural population analysis (NPA), and molecular electrostatic potential map (MEP). 31 The Nonlinear optics (NLO), and correlation between experimental and computed 1 H NMR values were calculated on the Gaussian 09 package.…”