Structural, spectroscopic, and theoretical investigations of (E)–methyl–3–(3,5–di–tert–butyl–2–hydroxybenzylideneamino)–4–methylbenzoate

Abstract

A novel Schiff base ((E)–methyl–3–(3,5–di–tert–butyl–2–hydroxybenzylideneamino)–4–methylbenzoate (MDM), C24H31NO3) at phenol–imine form with the OH⋯N intra–molecular hydrogen bond was synthesized. Its structural and spectroscopic characterizations were performed by using experimental (single crystal X–ray diffraction, Fourier transform infrared [FT–IR], NMR chemical shift, and UV–vis spectroscopies) and theoretical (DFT/B3LYP/6‐311+G[2d,p] computational level) methods. X–ray diffraction investigation shows that the MDM crystallized in phenol–imine form with OH⋯N intra–molecular hydrogen bond. Detailed investigations of the presence and nature of the inter–molecular contacts within solid state crystal packing form of MDM were examined by Hirshfeld surface analysis. The intra–molecular electronic transitions in the compound were investigated and determined by UV–vis electronic absorption wavelengths and FMOs analyses. The structural, vibrational, and NMR chemical shift analyses of azomethine (CHN) and phenolic hydroxyl (OH) groups in MDM supported its phenol–imine structural formation.