Supramolecular helical mesomorphic polymers. Chiral induction through H-bonding.
The work described here concerns a challenge of general interest in supramolecular chemistry: the achievement of chiral helical organizations with controlled structures. This work provides a strategy to obtain supramolecular polymers in which a chiral helical conformation has been induced by a noncovalent association, that is, through hydrogen bonding. Polycatenar 2,4,6-triarylamino-1,3,5-triazines, which organize into columnar mesophases and are susceptible to H-bonding interactions, were chosen as a starting point to build up the chiral supramolecular structure. The stacking of these mesogens has been forced to wind in a helical way by means of H-bond association with (R)-3-methyladipic acid, within the mesophase. The optically active columnar organization has been studied in depth by optical microscopy, differential scanning calorimetry (DSC), X-ray diffraction, and circular dichroism. Formation of stable complexes between the triazine units and (R)-3-methyladipic acid has also been investigated by means of NMR diffusion-ordered spectroscopy (DOSY) experiments in chloroform.
Barberá
Joaquín
J
Instituto de Ciencia de Materiales de Aragón, Consejo Superior de Investigaciones Científicas, and Química Orgánica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza, Spain.
Puig
Laura
L
Romero
Pilar
P
Serrano
José Luis
JL
Sierra
Teresa
T
D000272:Adipates / Q000737:chemistry*; D002942:Circular Dichroism; D006860:Hydrogen Bonding; D008958:Models, Molecular; D011108:Polymers / Q000737:chemistry*; D013237:Stereoisomerism; D014227:Triazines / Q000737:chemistry*; D014961:X-Ray Diffraction
D000272:Adipates; D011108:Polymers; D014227:Triazines; C033274:3-methyladipic acid