Design, synthesis, structural analysis, and DFT calculation Insights into the molecular architecture of amino substituted 4H-chromene scaffolds

Abstract

Amino-substituted 4H-chromene scaffolds, comprising nitrogen and oxygen, have garnered significant attention in modern organic chemistry due to their widespread applications in medicinal chemistry, drug discovery, and material sciences. This study demonstrates the synthesis and investigation of a series of 2-amino-3-cyano-4H-chromenes. The molecular structures of these compounds were established using X-ray diffraction, which revealed their supramolecular features. The fused 4H-chromene molecules crystallise in monoclinic and triclinic crystal systems with space groups P-1, P21/c, C2/c, and P21/n. These molecules show interactions like O-H...O, N-H...O, N-H...N, C-H...O, and C-H...N, along with this Pi-Pi stacking and C-H...Pi arrangements. Hirshfeld surface analysis confirmed the presence of these interactions, and 2D fingerprint plots quantified their contributions. The structural aspects of the compounds, including their optimised molecular geometry and intramolecular hydrogen bonding, were examined using Density Functional Theory (DFT). The constructed structures showed a strong correlation with experimental results. Additionally, the molecular electrostatic potential was studied to understand the energy distribution and chemically reactive regions of the molecules.