Chlorin e6 13(N)-methylamide-15,17-dimethyl ester and its nickel complex as the inducers of chiral nematic liquid crystals

Chiral Macroheterocycles as Inducers of Helical Liquid Crystals: Molecular Design, Specialty of Functioning

“…As for the remaining MHCs and their metal complexes, their macrocycles are strongly acoplanar, due to the nonaromatic nature of hemiporphyrazine (+)HPA and the presence of a saturated five-membered ring in the structure of the chlorin e6 derivative MADMECl and its complexes. In this case, the shape of the hemiporphyrazine is the most acoplanar, as evidenced by the values of the standard deviation of atoms from the NNNN plane of the macrocycle [25] (Table 1).…”

“…The subjects of study included nematic LCs and chiral MHCs of various structures: nickel complex of octa-substituted tetraphenylporphine (Ni-(+)TPP), [23] symmetric camphor-substituted hemiporphyrazine ((+)HPA), [24] nickel complex of tetracamphoropyrazinoporphyrazine (Ni(À )TPPA), chlorin e6 13(N)-methylamide-15,17-dimethyl ether (MADMECl) and its metal complexes (M-MADMECl), [25,26] the structure of which is presented in Scheme 1.…”

“…[23] -* -(+)HPA in CB6, -○-� HPA in CB6 [24] , -~-Ni(À )TPPA in CB6, -Δ-Ni(�)TPPA in CB6; b) -○-MADMECl in CB2; -~-Zn-MADMECl; -■-Cu-MADMECl; -* -Ni-MADMECl. [25,26] The main measure of the effect of a chiral dopant on a nematic matrix is the helical twisting power (HTP [27] ), calculated using the equation:…”

“…Both effects indicate the formation of a helix and the induction of chiral nematics [23,25,26] . Analysis of textures at different temperatures and concentrations of dopants allowed measurement of clearance temperature T N*I (phase transition N*→I) and calculate the slopes of phase diagrams (Figure 3) β=dT*/dc (T*=T N*I /T o , where T o is the clearance temperature of the nematic.…”

“…Figure 4. Structures of solvates of chiral MHC with two alkoxycyanobiphenyl molecules (a) NiÀ R (+) TPP[23] and (b) Ni-MADMECl [25]. …”