Supramolecular architectures of conformationally controlled 1,3-phenyl-dioxalamic molecular clefts through hydrogen bonding and steric restraints

摘要: In this contribution the supramolecular architecture of a series six 1,3-phenyl-dioxalamic molecular clefts is described. The conformation was controlled by use Me and OMe group substitution in phenyl spacer. structural conformational study carried out X-ray diffraction analysis, DFT calculations at PBEPBE 6-31+G (3df, 3pd) theory level variable temperature 1H NMR solution. C2-Me exerts dual influence on adopting endo(sc) or exo(ac) conformations oxalamic arms, meanwhile C2-OMe leads to adoption exo(ap) conformation. results showed that exo(ap)–exo(ap) more stable than other due conjugation stabilizes molecule minimizes energy. Supramolecular arrays oxalamate/oxalamide derivatives 1,3-diaminobenzene, 2-methyl-benzene-1,3-diamine 2,4,6-trimethyl-benzene-1,3-diamine are directed self-complementary N–H⋯O hydrogen bonding interactions, whose organization crystal depends twist 5-tert-butyl-2,6-diamineanisol with an conformation, π-stacking, dipolar carbonyl–carbonyl interactions C–H⋯O soft contacts. N1,N1′-(1,3-(2,4,6-Trimethyl)-phenyl)-bis-(N2-(2-(2-hydroxyethoxy)ethyl)oxalamide) adopts form meso-helix, which first example helical 1,3-phenyl-dioxalamide.