Intramolecular H⋯H steric hindrance modulated aggregate packing and optoelectronic properties in 1-naphthyl, 9-anthryl end-capped styrylarylene derivatives

Abstract

The crystal structures and optoelectronic properties of the compounds 1,4-bis[2-(1-naphthyl)vinyl] benzene (BNVB), 4,4 0 -bis[2-(1-naphthyl)vinyl]biphenyl (BNVBP) and 4,4 0 -bis[2-(9-anthryl)vinyl] biphenyl (BAVBP) were studied and compared. Due to intramolecular H/H steric hindrance, BAVBP molecules adopt a twisted conformation and constructed into a three-dimensional C-H/p interacting structure. In contrast, the H/H steric hindrance is alleviated in compounds BNVB and BNVBP. Both molecules have much better planar character and aggregate into a lamellar structure with a herringbone packing motif. The aggregate structure exerts a dramatic influence on the optoelectronic properties.Compound BAVBP shows an aggregation-induced enhanced emission (AIEE) character. While, both BNVB and BNVBP are AIEE-inactive, BNVBP displays moderate hole-transporting ability. Results and discussions SynthesisAll the compounds were easily prepared by one-step Horner-Emmons or Wittig reactions similar to the reported procedures. 5

Substitution degree engineering the crystal packing and optoelectronic properties of benzofuranvinyl-substituted benzene-cored derivatives

“…1d The low OFET performance of 2BFVB is possibly due to the still short p- With the improved p-conjugation length the carrier-mobility increases from 10 À6 cm 2 V À1 s À1 to 10 À3 cm 2 V À1 s À1 . 14 As shown in Fig. 6, both 2BFVB and 3BFVB can form a crystalline lm on OTS-pretreated SiO 2 at 60 C. However, the carrier-transport ability of 3BFVB is much lower than that of 2BFVB.…”

“…This is different from 4,4 0 -bis[2-(1-naphthyl) vinyl]benzene, which has a classical herringbone packing structure. 14 Overall, 2BFVB is a kind of 2D semiconductor.…”

“…Though the 2BFVB molecules stack into a herringbone-arranged H-aggregate in the crystalline solid, they do not suffer from an aggregation-caused quenching effect, which was usually observed in the H-aggregates. 14,16 The quantum yield of the 2BFVB crystalline solid is as high as 76%, and ranks amongst the highly luminescent Haggregates. 17 The high emission efficiency of the 2BFVB crystals may be closely related to the two molecular geometries in the crystal structure.…”

Facile fabrication of AIE/AIEE-active fluorescent nanoparticles based on barbituric for cell imaging applications

“…All the molecules exhibit distorted conformation due to the intramolecular steric hindrance. 39 The optimized geometric structure of 1 show twisted conformation with a dihedral angle of 56.63 (Fig. S17 †).…”

Substitution position tuning of the different aggregation-induced emission properties of four (1-naphthyl)vinyl(9-anthryl)vinylbenzene isomers: from ACQ to AIEE and AIE

“…For example, Tang's group reported that the E-Z isomerization may be not involved in the AIE process of stilbene derivatives. 4 Now it is generalized that the AIE process may be dependent on many factors, such as the molecule's planarity, 1b steric hindrance, 5 intramolecular rotation, 6 or intermolecular interactions. 3 So far, most AIE studies emphasize the role of the solid-state character in the emission enhancement.…”