Aggregation-Induced Emission of Contorted Polycondensed Aromatic Hydrocarbons Made by Edge Extension Using a Palladium-Catalyzed Cyclopentannulation Reaction

Abstract

Contorted polycyclic aromatic hydrocarbons (PAHs), CPA1–2 and CPB1–2, bearing peripheral five-membered rings were synthesized employing a palladium-catalyzed cyclopentannulation reaction using specially designed diaryl acetylene synthons TPE and TPEN with commercially available dibromo- anthracene DBA and bianthracene DBBA derivatives. The resulting target compounds CPA1–2 and CPB1–2 were isolated in excellent yield and found to be highly soluble in common organic solvents, which allowed for their structural characterization and investigation of the photophysical properties, disclosing their aggregation-induced emission (AIE) properties in THF at selective concentration ranges of water fractions in the solvent mixture. Examination of the contorted PAH structures by means of density functional theory (DFT) revealed higher electronic conjugation in the more rigid and planar anthracene-containing CPA1–2 derivatives when compared to the twisted bianthracene-bearing moieties CBPA1–2 with HOMO–LUMO bandgaps (ΔE) of ∼2.32 eV for the former PAHs and ∼2.78 eV for the latter ones.

High Uptake of the Carcinogenic Pararosaniline Hydrochloride Dye from Water Using Carbazole-Containing Conjugated Copolymers Synthesized from a One-Pot Cyclopentannulation Reaction

“…Polycyclic aromatic hydrocarbons (PAHs) have gained significant interest as prominent building blocks for various applications, among others, the design of conjugated macromolecules due to their large π surface and planarity. − PAHs bearing interchangeable arrangements of five- and six- membered rings are described in the literature with various taxonomies, among others, cyclopenta-fused PAHs (CP-PAHs), , nonalternant conjugated polycyclic hydrocarbons (CPHs), or conjugated compounds bearing quinoidal groups . The high chemical, physical, and biological properties of CP-PAHs promote them as active component for myriad applications, ranging from optoelectronics, like, organic photovoltaic cells (OPVs), , organic field-effect transistors (OFETs), and light-emitting diodes (LEDs), to medical therapeutics, like their use in DNA intercalators for chemotherapy .…”

Efficient Iodine Uptake of Ultra Thermally Stable Conjugated Copolymers Bearing Biaceanthrylenyl Moieties and Contorted Aromatic Units Using a [3 + 2] Palladium-Catalyzed Cyclopolymerization Reaction

“…11,12 Conjugated copolymers made from [3 + 2] cyclopolymerization reactions have gotten noticeable interest as potential components for organic electronics 13,14 as they are characterized by unique structural features where the cyclopentannulated rings are incorporated into the backbone of the conjugated chains, 15,16 thus improving the polymers' structural rigidity and planarity, consequently enhancing the charge delocalization along the macromolecular chain. 17 Several studies have reported the synthesis of cyclopentannulated copolymers with remarkable optical and electrochemical properties for applications in optoelectronics. 14,18−20 It is noteworthy that our group has been the first to report the synthesis of specially designed cyclopentannulated copolymers as adsorbent materials revealing high uptake capacity of iodine and toxic organic dyes.…”

“…The feasibility of the reaction was tested by making three prototypical monomers synthesized, as can be noticed from Scheme 1 which describes the synthetic pathway for derivatives BCM1−3. These building blocks were made by reacting 2 equiv of 9-bromoanthracene 1 with each of the contorted diethynyl aryl surrogates 2a−c using a typical cyclopentannulation reaction procedure17 which employs a catalytic amount of pd 2 (dba) 3 and P(o-tol) 3 in the presence of 5 equiv of KOAc and 2 equiv of LiCl in a deoxygenated 1:1 mixture of DMF/ toluene at 130 °C under argon for 1 day, thus providing 73− 95% of the target products in high purity, as confirmed by various analytical techniques such as NMR ( 1 H and 13 C), ESI-MS, and FTIR spectra (Figures S1−S3, S7−S9, S15−S20 in the Supporting Information file).…”

Polycyclic Aromatic Hydrocarbon‐based Soft Materials: Applications in Fluorescent Detection, Gelation, AIEE and Mechanochromism

“…PAHs are highly emissive with the long fluorescence lifetime and high quantum yield [35–37] . However, in the solid state, PAHs suffer greatly from π‐aggregation and excimer formation resulting in low photoluminescence (PL) and low quantum yield [7,38] . This drawback is known as the aggregation‐caused quenching (ACQ) [39,40] .…”

“…[35][36][37] However, in the solid state, PAHs suffer greatly from π-aggregation and excimer formation resulting in low photoluminescence (PL) and low quantum yield. [7,38] This drawback is known as the aggregation-caused quenching (ACQ). [39,40] The ACQ property of luminogens makes them inefficient to be employed in the optoelectronic devices.…”