Hydrogen Bonding Patterns and DFT Studies of (4-Acetylphenyl)amino 2,2-Dimethylpropanoate and (E)-1-(4-Aminophenyl)-3-[4-(dimethylamino)phenyl]prop-2-en-1-one.

The (4-acetylphenyl)amino 2,2-dimethylpropanoate ( 1) and (E)-1-(4-aminophenyl)-3-[4-(dimethylamino)phenyl]prop-2-en-1-one ( 2), were synthesized and characterized by elemental analysis, FT-IR, H NMR, CNMR and single crystal X-ray diffraction techniques. Both compounds 1 and 2 crystallized in orthorhombic crystal system with Pbca and P212121 space group respectively, having the unit cell parameters: a = 11.7220(12) Å, b = 14.4580(13) Å, c = 15.7853(12) Å, β = 90°, Volume = 2675.2(4) Å, Z = 8 for 1 and a = 6.1146(5) Å, b = 9.0567(8) Å, c = 26.079(3) Å, β = 90°, Volume = 1444.2(2) Å, Z = 4 for compound 2. The crystal structures of both compounds ( 1 and 2) are stabilized by N-H···O strong intermolecular hydrogen bonding forming C( 8) motifs. In compound 1, the molecules are linked by three C-H···O intramolecular H-bond forming S( 6) motifs. In compound 2, the molecules are linked by C-H···N intermolecular H-bond exhibiting C( 12) motif and C-H···O intramolecular H-bond leading to S( 5) motif. Crystallographic and vibrational data are compared with the results of density functional theory (DFT) method at the B3LYP/6-31G(d,p) level. The electronic (UV-vis) spectra was calculated by using the TD-DFT method and correlated with experimental spectra. Graphical Abstract: The crystal structure of compound 1, formed four motifs which are giving first-level graph set N: C( 8) S( 6) S( 6) S( 6) while compound 2, formed three motifs, giving first-level graph set N: C( 8) C( 12) S( 5) and second-level graph set N( a, b): C( 14). Crystallographic and vibrational (IR) data were compared with the results of density functional theory (DFT) method at the B3LYP/6-31G(d,p) level and electronic (UV-vis) spectra was calculated by using the TD-DFT method.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]