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• 62-53-3 aniline 

Relevant academic research and scientific papers

Preferential formation of homochiral helical sandwich-shaped architectures through the metal-mediated assembly of tris(imidazoline) ligands with a set of d3-d10 transition-metal ions

A novel type of chiral trismonodentate imidazolinyl ligands ((S,S,S)-4 and (R,R,R)-4) has been achieved in good yields. The ligands show a strong tendency to induce the generation of the discrete sandwich-shaped M3L 2 architectures with programmed helicity through the edge-directed complexation with a series of d3-d10 transition-metal ions, while taking advantage of the steric hindrance of the bulky substituents of the imidazoline rings to avoid the formation of extended metal-organic frameworks (MOFs). In spite of different coordination geometries, monovalent metal ions (e.g. Ag+), divalent metal ions (e.g. Pd2+, Cu2+, Cd2+, Zn2+, Co2+, Mn 2+, and Ni2+), and even trivalent metal ions (e.g. Fe 3+ and Cr3+) exhibit isostructural coordination. Installation of stereo-centers fused onto the imidazoline rings results in favored handedness of the self-assemblies through the expression of molecular chirality into supramolecular helicity. In the crystal structures of [M 3{(S,S,S)-4}2], the self-assembly has to adopt the M form to relax the van der Waals repulsions of the phenyl and isopropyl groups. The replacement of (S,S,S)-A with (R,R,R)-4 exclusively affords the opposite helicity (P). These results should provide important insights for the design of chiral helical capsule-like assemblies.

Self-assembly of discrete homochiral, helical, hydrogen-bonded nanocages: From vesicles to microspheres and tubules capable of gelating solvents

The chiral tris-monodentate imidazolinyl ligands la-c exhibit a strong tendency to form the discrete, helical [2+3] nanocages 3 ([l2-2 3]) with tartaric acids 2. Circular dichroism (CD) spectra and theoretical calculations reveal that supramolecular handedness of capsulelike architectures is determined only by the chirality of the imidazolinyl ligands rather than tartaric acids. The chirality of imidazolinyl Ii-gands is transferred to the helicity of the complexes through the directed hydrogen bonds between the N3 atom of imidazoline rings and the carboxyl of tartaric acids. These hydrogen-bonded nanocages can spontaneously self-assemble into spherical vesicles, during which the hydrogen bonding that arises from the hydroxyl groups of tartaric acids plays a crucial issue. The vesicles formed by [{(S,S,S)-1a}2(2L)3] (3a) may further evolve into microspheres that gelate organic solvents after being aged at -20°C for 24 h, and can also be unprecedentedly transformed to tubular assemblies capable of rigidifying the solvents when subjected to ultrasound irradiation.