Second-order nonlinear optical responses of heptahelicene and heptathiahelicene derivatives

Hyper-Rayleigh Scattering as a New Chiroptical Method: Uncovering the Nonlinear Optical Activity of Aromatic Oligoamide Foldamers

“…31 Several helical -conjugated systems have also been shown to exhibit enhanced HRS response due to their intrinsic electronic delocalization. [32][33][34][35][36] However, there has been no report about a possible chiral effect on the NLO response of these systems mainly because of the difficulty in producing both enantiomeric forms. Among molecular helical structures, aromatic oligoamide foldamers are known to readily afford chiral self-organized architectures.…”

“…One successful approach has been to exploit the helicity of phenylene oligomers substituted with donor/acceptor groups . Several helical π-conjugated systems have also been shown to exhibit enhanced HRS response due to their intrinsic electronic delocalization. − However, there has been no report about a possible chiral effect on the NLO response of these systems mainly because of the difficulty in producing both enantiomeric forms.…”

Alternating oligo(o,p-phenylenes) via ruthenium catalyzed diol–diene benzannulation: orthogonality to cross-coupling enables de novo nanographene and PAH construction

“…40e , g It is worth noting that helicenes, particularly higher helicenes containing thiophenes, have attracted interest as chiral nonlinear optical materials. 42 To our knowledge, compound 14 is the first reported example of a picene-helicene hybrid and we believe its chiroptical properties will be of future interest.…”

Twisted Polycyclic Aromatic Systems Prepared by Annulation of Bis(arylethynyl)arenes with Biphenylboronic Acids

“…[8] Fusing more benzene rings forms [n]helicenes, [9] which are important motifs for chiralc atalysts, [10] circular polarized luminescence materials, [11] and nonlinear opticalm aterials. [12] For the synthesis of PAHs with fjord regions, oligoarylenes containing 9.10-diphenylphenanthrene moieties are promising precursors. Nowadays, phenanthrenes can be directly constructedb yt ransition-metal-catalyzed annulationo fb iphenyl derivatives with alkynes.…”

“…Regions composed of four fused benzene rings (fjord regions) are effective for twisting because of steric hindrance of the adjacent C−H bonds . Fusing more benzene rings forms [ n ]helicenes, which are important motifs for chiral catalysts, circular polarized luminescence materials, and nonlinear optical materials . For the synthesis of PAHs with fjord regions, oligoarylenes containing 9.10‐diphenylphenanthrene moieties are promising precursors.…”