RESUMO
In the crystal, the whole mol-ecule of the title compound, C14H12N4O7·0.224H2O, is nearly planar with a maximum deviation from the least-squares plane of 0.352â (1)â Å. The mol-ecular conformation is stabilized by an intra-molecular N-Hâ¯O hydrogen bond, generating an S(6) ring motif. In the crystal, mol-ecules are linked by centrosymmetric pairs of N-Hâ¯O hydrogen bonds, forming ribbons along the c-axis direction. These ribbons connected by van der Waals contacts, forming sheets parallel to the ac plane. There are also inter-molecular van der Waals contacts and and C-Hâ¯π inter-actions between the sheets. A Hirshfeld surface analysis indicates that the most prevalent inter-actions are Oâ¯H/Hâ¯O (41.2%), Hâ¯H (19.2%), Câ¯H/Hâ¯C (12.2%) and Câ¯O/ Oâ¯C (8.4%).
RESUMO
Two complexes [KLa(HL(1))2{(CH3)2NCHO}2(H2O)3] (1) and [Sm(H2O)9](E-H2L(2))3·2H2O (2) were synthesized by the reaction of lanthanum(III) and samarium(III) nitrates with potassium 3-(2-(2,4-dioxopentan-3-ylidene)hydrazinyl)-2-hydroxy-5-nitrobenzenesulfonate (KH2L(1)) and potassium (E,Z)-5-chloro-3-(2-(1,3-dioxo-1-phenylbutan-2-ylidene)hydrazinyl)-2-hydroxybenzenesulfonate (KH2L(2)), respectively. Both complexes were fully characterized by elemental analysis, IR, (1)H and (13)C NMR spectroscopy, ESI-MS and single-crystal X-ray diffraction. Cooperative E,ZâE isomerization of KH2L(2), induced by resonance assisted hydrogen bonding and ionic interactions, occurs upon the interaction with Sm(III). Catalytic activities of KH2L(1,2) and their lanthanide derivatives were evaluated in the Henry reaction of nitroethane with a variety of aromatic and aliphatic aldehydes. Good yields (up to 91%) and diastereoselectivities (syn/anti 3 : 1) were observed in the reactions catalyzed by 1 in water.