1449686-77-4

Upstream product

• 1449686-76-3 2-bromo-9-(4-octyloxyphenyl)-9-fluorene-9-ol 
• 73183-34-3 bis(pinacol)diborane 
• 106-41-2 4-bromo-phenol 
• 111-83-1 1-bromo-octane 
• 96693-05-9 1-bromo-4-octyloxybenzene 

Relevant academic research and scientific papers

Synergistic steric pairing effects of terfluorenes with ternary side groups on β-conformation transition: Experiments and computations

Rational molecular design has led to the achievement of β-conformations of terfluorenes that are usually difficult for oligoalkylfluorenes with less than 5 repeat units. Herein, under the guideline of synergistically molecular attractor-repulsor theory (SMART), we design four models of terfluorenes with the possibility of inducing β-conformation in the terfluorene 2,2′-(spiro[fluorene-9,9′-xanthene]-2,7-diyl) bis(9-(4-(octyloxy)phenyl)-fluoren-9-ol) (2O8-DPFOH-SFX) by manipulating the cooperative effects of steric hindrance, hydrogen bonding (HB) and van der Waals (vdW) forces after thermal annealing. For terfluorene 2O8-DPFOH-SFX, the two isomers, raceme and mesomer, with two side chains residing on the two sides and on the same side of the fluorene backbone, respectively, have different packing styles and hence different optical properties: only the raceme isomer could induce the formation of β-conformation. Due to the steric pairing effect of side chains on both sides and the cooperative interaction of the middle spiro[fluorene-9,9′-xanthene] (SFX) group, the racemes precisely interlace with each other and tend to adopt Δ-shaped stacking, which favors a planar π-conjugated structure for the raceme. This is rationalized by the larger content of planar conformations in the 2O8-DPFOH-SFX raceme, according to molecular dynamics (MD) simulations of the condensed phase. Thus, oligofluorenes with definite molecular structure can be considered as notable materials for gaining insight into the structure-property relationships for optical and electronics applications.

Iodide ion receptors: shape-persistent macrocycles ofsyn/anticonfigurations

This article reports a pair of rigid iodide ion macrocyclic receptors ofsyn/anticonfigurations. Single crystal X-ray analysis confirms the structure of thesyn-isomers, and1H Nuclear Magnetic Resonance (1H NMR) titration and ultraviolet-visible (UV-Vis) absorption are used to study the binding affinity of the isomers to halogen ions. Both the isomers show colorimetric and fluorescence recognition towards iodide anions in dichloromethane solution. By solving the association constants, it can be concluded that the interaction between theanti-isomer and iodide ions is relatively weaker than that in thesyn-isomer, and thesyn-isomer has much better recognition selectivity for I?in CH2Cl2than theanti-isomer. The results of the theoretical calculations show thatsyn/anticonfigurations bring about different orientations of the alkyl chains, leading to the larger steric hindrance of theanti-isomer to hinder the combination with iodide ions, and thesynconfigurations with relatively smaller steric hindrance can enhance the binding between the isomers and the iodide anions. A shape persistent macrocycle with a bound conformation can be looked at as a special case of conformational selection, and the results of this study indicate a local induced fit mechanism following a conformational selection in the recognition of iodide anions, and we anticipate that this work will help to understand these two dominant binding mechanisms in molecular recognition and have a certain reference value for designing better anion receptors.

Friedel-crafts bottom-up synthesis of fluorene-based soluble luminescent organic nanogrids

A series of fluorene-based grid molecules (so-called Grid fluorenes) have been synthesized by means of shape-supported cyclization, starting from H-shaped precursors via the alternative Friedel-Crafts reactions of fluorenols and Suzuki cross-coupling reactions with key cyclization yields up to 26%. Fluorenol approaches and nanogrids open a door to soluble one-, two-, or three-dimensional nanoporous polymers as next-generation polymer mechano-semiconductors facing a new era of consciousness.