Synthesis and Crystal Packing of trans‐Bis(2‐aminotroponato)palladium(II) Complexes Bearing Linear Alkyl Chains – Hard Lamellar Structures Self‐Locked by Cross‐Shaped Molecular Units

Abstract

The synthesis, structure, and three-dimensional lamellar array of a series of trans-bis(2-aminotroponato-κN,κO)palladium(II) complexes bearing linear alkyl chains (1a: n = 5; 1b: n = 8; 1c: n = 14; 1d: n = 16; 1e: n = 18, where n is the number of carbon atoms in the chain) attached to trans nitrogen donor atoms are described. The trans-coordination of the ligands, the cross-shaped molecular structures, and the crystal packing of 1b and 1c have been unequivocally established from single-crystal XRD studies. Highly regulated multilayered lamellar structures are observed for 1b and 1c, where every lamellar layer in the crystallographic ab plane, formed by π-stacking interactions of metal cores and van der Waals[a]

Alkyl substituent-dependent systematic change in cold crystallization of azo molecules

“…The longer-chain derivatives of 2,4-DM-2-Cn (n ¼ 15-18, 20) exhibited a solid-liquid transition. The strong van der Waals interactions between the long alkyl chains increased the crystallinity, [24][25][26][27][28] and induced crystallization of the compound during cooling. The change in the position of the alkyl substituent in 2,4-DM-4-Cn versus 2,4-DM-2-Cn resulted in variations in the thermal behavior, such as cold crystallization.…”

Helicity Control of Supramolecular Gel Fibers Consisting of an Achiral NiII Complex in a Chiral Nematic Solvent

“…To gain insight into the specific gelation properties of 1 a in the NLC phase and the N*LC‐controlled supramolecular chirality of the gel fibers, various aggregation states of 1 a obtained from mesogenic and nonmesogenic solvents were analyzed by powder XRD (PXRD). The PXRD patterns of solid 1 a prepared from nonmesogenic solvents such as n ‐hexane (Figure a) and toluene (Figure S8 in the Supporting Information) show a series of diffraction peaks repeated with an interval of 26.1–26.2 Å, which can be attributed to the typical lamella reflections of a multilayered structure ,. The PXRD pattern and the layer spacing ( d spacing) for 1 a (26.1–26.2 Å) are very similar to those of Pt analogue 3 a (26.5 Å) in the crystalline state obtained by recrystallization from benzene/ n ‐hexane .…”