Supporting Information for: "Short Intramolecular O···O Contact in Some o-Dialkoxybenzene Derivatives Generates Efficient Hydrogen Bonding Acceptor Area"

Abstract

CSD refcodes and additional plots from the CSD search: distribution of relevant distances and torsion and dihedral angles. EP distribution within different crystal structures containing the o-dialkoxybenzene fragment. Examples of crystal structures with multiple hydrogen bonding interactions to O···O systems. Figure S1. Distribution of torsion angle O1a−C3a−C3b−O1b showing the preferentially coplanar arrangement of the two ether oxygen atoms with respect to the benzene ring. Figure S2. Plot of torsion angles C1a−O1a−C3a−C3b vs. C1b−O1b−C3b−C3a. Figure S3. Additional fragments used in CSD search. Figure S4. Distribution of corresponding O...O distances in transition metal complexes. Figure S5. Distribution of angles: C4-C3-O1 and O1-C3a-C3b i.e. O1-C3b-C3a in the extracted crystal structures shows significant deviation from the expected value of 120°. Figure S6. Distribution of dihedral angles between the C3/O1/C1 planes reflects the coplanar orientation of the oxygen electron pairs in the extracted crystal structures. Figure S7. Laplacian distribution in relevant planes of DMB system. Fugre S8. Comparison of the negative EP isosurfaces of DMB and anisole. Figure S9. EP distribution in meta- and para-DMB. Figure S10. Examples of EP distribution in different crystal structures containing the odialkoxybenzene fragment. Figure S11. Examples of multiple hydrogen bonding interactions to O...O system (O…H ≤ 3.0 Å and D−H...O ≥ 110°). Figure S12. CSD-based spatial distribution of D–H donors around O…O system. IsoStar plots are given for D–H…O interactions with O…H distances up to 2.6 Å. Figure S13. Distribution of O…H distances from O–H…O and N–H…O interactions. Figure S14. Distribution of the H atoms belonging to OH/NH donor groups with respect to the O…O acceptor plane (P1). Figure S15. Molecular graph showing the bond paths and bond critical points corresponding to the interactions of O...O acceptor system in crystal structures: RABWIA, FOTKUW and ITUCEG. Figure S16. Scatterplot O1a…H vs. O1b…H, where H is a single hydrogen atom potentially involved in a bifurcated hydrogen bond. Figure S17. Distribution of the H atoms belonging to BFHB with regard to the O…O acceptor plane. Figure S18. Scatterplot of D–H...O interaction angles in BFHB. Figure S19. Distribution of O...H contacts from BFHB. Figure S20. EP distribution in catechol molecule with and without an intramolecular hydrogen bond. Figure S21. EP distribution in guaiacol molecule with and without an intramolecular hydrogen bond. Figure S22. 3D representation of HOMO and LUMO orbitals in DMB in the ground electronic state obtained at the BP86(D)/TZ2P level of theory. Figure S23. Optimized geometry of the DMB-H2O dimer computed at the B3LYP/6-311++g(d,p) level of theory. Figure S24. Geometry of the transition state TS1 optimized at the B3LYP/6-311++G(d,p) level of theory. Table S1. Selected molecular parameters of the equilibrium geometry of the most stable conformer of DMB. Comparison between optimized values obtained at the B3LYP/aug-cc-pVTZ level and the gas-phase electron diffraction (GED) data. Table S2. CSD refcodes of the examined crystal structures.