Introduction Of Alkyl Groups Research Articles

Light-Induced, Cs2CO3 Promoted C-S Cleavage of Heteroaryl Sulfones for Benzyl Heteroarylation of [1.1.1]Propellane.

In this study, we developed a light-induced difunctionalization of [1.1.1]propellane with heteroaryl sulfones acting as difunctional reagents, allowing the introduction of alkyl and heteroaryl units across bicyclo[1.1.1]pentane frameworks. It features a broad substrate scope and can be used to functionalize structurally complex natural products. Mechanistic investigations indicate the Cs2CO3 promoted homolytic cleavage of heteroaryl sulfone C-S bonds by light. Moreover, the benzothiazolyl moiety in the products can serve as a formyl precursor, indicating the robust transformability of the products, owing to the ability of aldehydes to undergo a wide variety of organic transformations.

Effect of isopropyl chloride addition in AlCl3 catalytic system on the formation of coal tar pitch-based mesophases

Mesophase pitch is a high-quality precursor for the synthesis of high-performance pitch-based carbon fibers. The mesophase content, texture and softening point are the most important factors for the structure, properties and spinnability of mesophase pitch (MP). Herein, we report a novel approach for the preparation of mesophase pitch with high anisotropic content and low softening point by AlCl3 catalytic pyrolysis in the presence of isopropyl chloride (PrCl). The variation of anisotropic content and mesophase texture under different PrCl additions and the effect of the introduction of isopropyl on the molecular stacking of aromatic lamellar molecules were investigated. The results confirmed that, except for their role in improving catalytic activity, carbocation co-catalysts can improve the structure and molecular assembly of aromatic molecules through the introduction of alkyl groups. The reaction of isopropyl chloride (PrCl) as a co-catalyst catalyzed pyrolysis of medium-temperature coal pitch at 370 ℃ for 8 h produced a bulk mesophase with a content close to 100 %. Compared to the AlCl3 system (without PrCl), the AlCl3-PrCl system can catalyze the preparation of mesophases at lower temperatures. In addition, it is logical that the introduction of isopropyl group significantly increases the stacking spacing of the mesophase pitch layer molecules, which can effectively improve the mobility of the aromatic layer molecules resulting in the growth of mesophase. The fusion texture and anisotropic content of mesophase pitch were significantly improved by replacing the nucleophilic reagent of the AlCl3-catalyzed system. This work provides feasible ideas for the preparation of high-performance coal tar based mesophase pitch.

Atomic symmetry alteration in carbon nitride to modulate charge distribution for efficient photocatalysis

The periodical distribution of N and C atoms in the carbon nitride skeleton results in intrinsically insufficient light absorption and serious carrier recombination. Herein, an efficient two-step cystine-mediated strategy was developed to alter the structure symmetry of C3N4 via the introduction of alkyl groups and nitrogen vacancies. The experimental analysis and theoretical calculation confirm that the formation of alkyl groups and nitrogen vacancies can modulate band structure and activate n-π* electron transition. Especially, the charge density in CN-25CYS is redistributed with spatial separation of oxidation and reduction sites, suppressing photogenerated charge recombination effectively. Therefore, the distorted carbon nitride (CN-25CYS) exhibits 9.6-times and 15.6-times higher photoreaction rates in hydrogen production and RhB degradation than the pristine one (CN-0CYS), respectively.

(Digital Presentation) Electro-Oxidative Trimerization of Catechol to Hexahydroxytriphenylene Using a Flow Microreactor

Due to their unique spectroscopic and geometric features, discotic liquid crystals (DLCs) have a variety of possible applications, including optical compensation films for liquid crystal displays, organic semiconductors for electronic devices, organic light-emitting diodes (OLEDs), and organic photovoltaic cells (OPVs).The most basic molecular structure of DLC is that of a triphenylene core surrounded by alkoxy and acyloxy groups. Even today, triphenylene with 2,3,6,7,10,11-hexaalkoxy and acyloxy groups is considered to be a common structural motif of DLC, and is undergoing rapid development. Until the 1990s, many studies had been reported on the synthesis of these hexasubstituted triphenylenes by trimerization of 1,2-disubstituted benzenes, but these protocols were not practical industrially due to the limitation of substituents, lack of reproducibility, the need for strict temperature control at -80°C, and poor solubility of reagents. Hence, today, the introduction of alkyl or acyl groups into 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) has become a common synthetic strategy for hexasubstituted triphenylene. Therefore, HHTP is an important starting material for the synthesis of various types of hexasubstituted triphenylene.HHTP was conventionally synthesized by oxidative trimerization of 1,2-dimethoxybenzene followed by demethylation of the resulting hexamethoxytriphenylene. However, this method required the use of at least a stoichiometric amount of sulfuric acid, which generated a large amount of waste acid. Therefore, the development of more efficient methods, such as trimerization of 1,2-dihydroxybenzene (catechol) to HHTP, has been actively studied in recent years. Kobori et al. synthesized HHTP in 70-76% yield by oxidative trimerization of catechol using FeCl3 as an oxidant. However, the HHTP product was contaminated with Fe impurities, which was undesirable for the application of DLC in the display and semiconductor industries. Furthermore, this protocol includes a reduction step of peroxidized HHTP (quinone), which accounts for 40-60% of the total HHTP yields. Some other protocols do not use metal reagents, but they use 60-80 wt% H2SO4 aq., which result in a large amount of waste acid.On the other hand, we have recently developed an efficient method for aromatic C,C-coupling reactions by electrochemical oxidation in a flow microreactor. In this synthetic method, peroxidation of the products can be avoided by controlling the residence time in the reactor. In addition, electrochemical oxidation can be carried out without the use of oxidants or catalysts. Thus, this synthetic method has many features to overcome the drawbacks of conventional methods.In this study, we have successfully carried out the electro-oxidative trimerization of catechol in a flow microreactor to synthesize HHTP efficiently without the need for metallic reagents and reduction procedures.As a result, HHTP was obtained in 20% yield using 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) as a solvent. The results showed that the radical cations of catechol, which were generated on the anode surface, proceeds C,C-coupling in HFIP. On the other hand, the yield decreased to 4% or 0% when HFIP/H2O mixed solvents were used. DFT calculation suggested that the proton dissociation equilibrium of catechol intermediate greatly affects the reaction mechanism. We calculated the pK a values of catechol intermediate in each HFIP/H2O solvent composition, and discussed the effect of H2O contamination on the HHTP yield. Figure 1

Alkyl-promoted iridium complex for high-performance deep-red phosphorescent organic light-emitting diodes

In this work, a novel deep-red (642 nm) iridium complex, Ir(bp4b)2(dend), is developed. The introduction of alkyl groups in ligands weakens the intermolecular interactions and endows Ir(bp4b)2(dend) with favorable physical properties: short photoluminescence lifetime (271.6 ns), low concentration sensitivity (10−6 to 10−4 M) and balanced charge-transporting ability. Ir(bp4b)2(dend)-doped phosphorescent device displays high efficiencies (9.62 cd/A, 12.25 lm/W, 15.29%), low roll-off of efficiencies (from 10 to 1000 cd/m2: no decrease; from 1000 to 5000 cd/m2: 10.6%), relatively low concentration sensitivity (from 5% to 15%), long device lifetime (T80: 5225 h at 100 cd/m2) and very stable electroluminescent spectra (from 1 cd/m2 to maximum luminance). This performance is comparable to those of previous record deep-red (around 640 nm) phosphorescent emitters. More importantly, compared with previous record emitters, Ir(bp4b)2(dend) reports more kinds of excellent parameters and such comprehensive deep-red emitter is rare at present.

Introduction of alkyl and sulfonic groups in Ti-metal-organic framework for boosting removal of metformin hydrochloride

Removal of metformin hydrochloride (Met•HCl) is necessary but still faces challenges. Our work reported a new adsorbent (MIL-125-NH-RSO3H, R = CH2CH2CH2), constructed via the post-synthesis covalent reaction between MIL-125-NH2 and 1,3-propanesultone. Compared with the pristine MIL-125-NH2, the newly obtained material shows improved negative surface property and enhanced hydrophobicity, ascribed to the contributions from -SO3H and the alkyl groups respectively. As a result, the adsorption capacity of MIL-125-NH-RSO3H can reach 164 mg•g−1, superior to the unmodified sample and other reported porous materials. The adsorption behavior follows the Langmuir model and pseudo-second-order model. The adsorbent possesses excellent anti-interference ability from co-existing salts and can be well regenerated through a simple elution method. Therefore, our work provides a new sight to construct high-efficiency adsorbents by simultaneously improving various host-guest interactions.

Quaternary ammonium immobilized PAMAM as efficient catalysts for conversion of carbon dioxide

Fixation of CO2 with epoxides to generate cyclic carbonates is an essential reaction. The co-catalysts free catalytic conversion of CO2 without metals and solvents is still challenge. Herein, a new series of quaternary ammonium immobilized polyamidoamines (PAMAMs) with hydroxylamino groups were fabricated from reaction of third generation PAMAM dendrimer with glycidyl alkyl dimethylammonium bromide originated from varied tertiary amine with epibromohydrin, which were characterized by FT-IR, TGA, 1H NMR, SEM and XPS, and CO2 adsorption was also observed. These polymers were considered as efficient catalyst for CO2 fixation reaction in the absence of co-catalysts and solvent conditions. Catalytic performances demonstrated that the introduced alkyl groups connected on polymers backbone exhibited crucial effect on catalytic activity, especially, [G3-PAMAM-HADMAB-Cn]Br could effectively catalyzed CO2 fixation with various epoxides under optimized conditions, and corresponding cyclic carbonates can reached at excellent yields. Furthermore, a proposed catalytic mechanism was elucidated on the experimental results and density functional theory (DFT), which indicates that hydrogen bonding play a significant role in activating epoxide and CO2.

Tuning the CO2 absorption and physicochemical properties of K+ chelated dual functional ionic liquids by changing the structure of primary alkanolamine ligands

To reveal the effects of the alkyl substitutions at alpha (α) or beta (β) position adjacent to amino group of primary alkanolamine ligands on CO2 absorption and physicochemical properties of metal chelated dual functional ionic liquids (DFILs), four DFILs were prepared by reacting potassium imidazole salt (KIm) with alkanolamine ligands, including 2-amino-2-methyl-1-propanol (AMP), 2-amino-1-butanol (AMB), DL-1-amino-2-propanol (DLAMP), and monoethanolamine (MEA). CO2 absorption behavior and mechanism of DFILs were studied, and density (ρ), speed of sound (u), and viscosity (η) of DFILs were measured to correlate with the CO2 absorption performance. DFT calculations were employed to explore the influence of the interactions between K+ and alkanolamine on the CO2 absorption and physicochemical properties of DFILs. The results show that CO2 capacity at 333.2 K is as follows: [K(AMP)2][Im] > [K(AMB)2][Im] > [K(DLAMP)2][Im] > [K(MEA)2][Im], indicating that the introduction of alkyl group at α or β position of alkanolamines can enhance CO2 capacity, and the effect of the α position is more significant than the β position. Both ρ and u follow the order: [K(AMP)2][Im] < [K(AMB)2][Im] < [K(DLAMP)2][Im] < [K(MEA)2][Im], while η is in the reverse order. Moreover, the saturated CO2 capacity of DFILs has an approximately linear relation with the thermal expansion coefficient. DFT calculations show that the presence of the alkyl group at α or β position of alkanolamines reduces the Mulliken charge of N and O atom, thereby weakening the cation coordination interaction between K+ with ligand, resulting in the decrease in ρ and u of DFILs. Moreover, the decrease in the Mulliken charge of N and O atom in alkanolamine leads to the increase of chelated cation-[Im]− interaction, thereby increasing η of DFILs. Consequently, [K(AMP)2][Im] exhibits higher CO2 capacity and good reversibility, due to the fact that CO2 can react with the chelated cation and [Im]– simultaneously. The present study provides a new method for effectively regulating the performance of DFILs.

Molecular arrangement in diphenylanthracene derivative films deposited under vacuum on in-plane oriented polythiophene films

Molecular arrangements of 9,10-diphenylanthracene (DPA) and its derivatives inside films deposited under vacuum were investigated. Two DPA derivatives with alkyl chains, 9,10-Bis(4-methylphenyl)anthracene (diMe-DPA) and 9,10-Bis(4-octylphenyl)anthracene (diOct-DPA), were synthesized and structural analyses of their single crystals were performed. It was clarified that anthracene frames of diMe-DPA and diOct-DPA were arranged uniaxially inside the single crystals by introducing alkyl groups to the DPA. Thin films of these molecules were formed by evaporating them under vacuum on glass substrates and polythiophene (PT) films, in which PT chains were uniaxially aligned parallel to the substrates. The angle between anthracene frames of diMe-DPA and the substrate plane of the PT/glass was smaller than that on the glass substrates. In-plane molecular arrangements were also evaluated, and it was clarified that short axes of the anthracene frames inside diMe-DPA and diOct-DPA were nearly parallel to the PT molecular chain direction.

Xanthenylacetic Acid Derivatives Effectively Target Lysophosphatidic Acid Receptor 6 to Inhibit Hepatocellular Carcinoma Cell Growth.

Despite the increasing incidence of hepatocellular carcinoma (HCC) worldwide, current pharmacological treatments are still unsatisfactory. We have previously shown that lysophosphatidic acid receptor 6 (LPAR6) supports HCC growth and that 9-xanthenylacetic acid (XAA) acts as an LPAR6 antagonist inhibiting HCC growth without toxicity. Here, we synthesized four novel XAA derivatives, (±)-2-(9H-xanthen-9-yl)propanoic acid (compound 4 - MC9), (±)-2-(9H-xanthen-9-yl)butanoic acid (compound 5 - MC6), (±)-2-(9H-xanthen-9-yl)hexanoic acid (compound 7 - MC11), and (±)-2-(9H-xanthen-9-yl)octanoic acid (compound 8 - MC12, sodium salt) by introducing alkyl groups of increasing length at the acetic α-carbon atom. Two of these compounds were characterized by X-ray powder diffraction and quantum mechanical calculations, while molecular docking simulations suggested their enantioselectivity for LPAR6. Biological data showed anti-HCC activity for all XAA derivatives, with the maximum effect observed for MC11. Our findings support the view that increasing the length of the alkyl group improves the inhibitory action of XAA and that enantioselectivity can be exploited for designing novel and more effective XAA-based LPAR6 antagonists.

D-π-D type fluorescent compounds based on dehydroabietic acid triarylamine: Synthesis, photophysical properties and application as hole-transporting materials in perovskite solar cells

D-π-D hole-transporting materials have the potential to be excellent dopant-free hole-transporting materials (HTMs) for perovskite solar cells (PSCs) because of their tunable energy levels, high charge mobility, good solubility, and excellent film-forming properties. In this paper, two series of D-π-D type compounds, Series 1 (2TPA-CZ1~2TPA-CZ3) and Series 2 (2DTPA-CZ1~2DTPA-CZ3), were synthesized by linking a carbazole derivative (as a π-bridge) to triaryamine or dehydroabietic acid triarylamine groups (the donor groups) via C–C coupling reactions. The optical, electrochemical, thermal, and photovoltaic properties in PSCs of these compounds were fully investigated. The two series of compounds exhibit good ultraviolet absorption, fluorescence emission, and electrochemical and thermal properties. In addition, their highest occupied molecular orbital levels and energy gaps make them suitable for use as hole-transporting materials in PSCs. Among the PSCs developed, Device 1, based on 2TPA-CZ1, showed the best performance, with a power conversion efficiency (PCE) of 12.27%, a open circuit voltage (VOC) of 1.13 V, a short-circuit photocurrent density (JSC) of 15.10 mA cm−2, and a fill factor (FF) of 71.61%, which is comparable to that of a device based on the conventional hole-transporting material Spiro-OMeTAD. While the PCE of Devices 4–6 was lower than the PCE of Devices 1–3, Devices 4–6 exhibit better stability. This may be due to the higher Tg and better film-forming properties of compounds formed using the dehydroabietic acid skeleton. In additional, the introduction of alkyl groups on the carbazole moiety decreased the efficiency of the PSC devices. These results demonstrate that the 2TPA-CZ1 compounds are promising HTMs for PSC applications.

Elongation of the side chain by linear alkyl groups increases the potency of salacinol, a potent α-glucosidase inhibitor from the Ayurvedic traditional medicine “Salacia,” against human intestinal maltase

Four chain-extended analogs (12a–12d) and two related de-O-sulfonated analogs (13a and 13c) by introducing alkyl groups (a: R = C3H7, b R = C6H13, c: R = C8H17, d: R = C10H21) to the side chains of salacinol (1), a natural α-glucosidase inhibitor from Ayurvedic traditional medicine “Salacia”, were synthesized. The α-glucosidase inhibitory activities of all the synthesized analogs were evaluated in vitro. Against human intestinal maltase, the inhibitory activities of 12a and 13a with seven-carbon side chain were equal to that of 1. In contrast, analogs (12b–12d, and 13c) exhibited higher level of inhibitory activity against the same enzyme than 1 and had equal or higher potency than those of the clinically used anti-diabetics, voglibose, acarbose, and miglitol. Thus, elongation of the side chains of 1 was effective for specifically increasing the inhibitory activity against human intestinal maltase.

Hydroxylamino‐Anchored Poly(Ionic Liquid)s for CO2 Fixation into Cyclic Carbonates at Mild Conditions

AbstractCatalytic utilization of CO2 addition into chemicals has potential as a strategy for removing CO2 from the atmosphere. In this context the additive‐free catalytic conversion of CO2 into cyclic carbonates in the absence of metal and solvents under mild conditions is a major challenge. Herein, a series of hydroxylamino‐tethered polymeric ionic liquids bearing adjustable alkyl length substitutes are constructed from copolymerization of divinyl benzene and vicinal hydroxyl and amino base monomeric ionic liquids synthesized from 1‐glycidyl‐3‐vinylimidazolium bromide with alkyl amine. The polymeric ionic liquids are used in CO2‐epoxide cycloaddition reactions to prepare cyclic carbonates and demonstrate high efficiency and stable reusability without a co‐catalyst under atmospheric pressure and under solvent‐free conditions. The introduction of alkyl groups on an ionic polymer host backbone can accelerate the reaction process. A preliminary kinetic study is performed using [PDVB‐HAVIM‐C18]Br and the activation energy is calculated as 53.2 kJ mol−1. A hydrogen bonding and Br– ion synergistic catalytic mechanism is proposed to account for the excellent catalytic activity of the synthesized ionic polymer.

Tunable LCST/UCST-Type Polypeptoids and Their Structure-Property Relationship.

Bioinspired thermoresponsive polymeric materials with tunable phase-transition behaviors are highly desirable for biomedical applications. Here, we reported a facile approach for the synthesis of both lower critical solution temperature (LCST) and upper critical solution temperature (UCST) types of thermoresponsive polypeptoids with tunable phase-transition temperature in the range of 29--55 °C. The introduction of alkyl groups and ethylene glycol (EG) units results in a controlled phase-transition behavior under fairly mild conditions. A very sharp transition (ΔT ≤ 1.5 °C) is observed by simply adjusting pH and the alkyl chain length. In particular, the carboxyl-containing polypeptoids display designable UCST behavior, which can be finely tuned in both water and methanol. All these features make the obtained polymers beneficial for practical applications. More interestingly, we demonstrate that the hydrophilic EG group behaves as an excellent regulator to tune the UCST behavior, while the hydrophobic alkyl residues show remarkable capability to regulate the LCST behavior of the system. We hope that such systematic structure-property studies will enable the design of smart polymer materials to meet the specific needs of future applications.

Molecular Packing and Solid-State Photophysical Properties of 1,3,6,8-Tetraalkylpyrenes.

The relationship between the photophysical properties and molecular orientation of 1,3,6,8-tetraalkylpyrenes in the solid state is described herein. The introduction of alkyl groups with different chain structures (in terms of length and branching) did not affect the photophysical properties in solution, but significantly shifted the emission wavelengths and fluorescence quantum yields in the solid state for some samples. Pyrenes bearing ethyl, isobutyl, or neopentyl groups at the 1-, 3-, 6-, and 8-positions showed similar emission profiles in both the solution and solid states. In contrast, pyrenes bearing other alkyl groups exhibited an excimer emission in the solid state, similar to that of the parent pyrene. On studying the photophysical properties in the solid state with respect to the obtained crystal structures, the observed solid-state photophysical properties were found to depend on the relative position of the pyrene chromophores. The solid-state photophysical properties can be controlled by the alkyl groups, which provide changing crystal packing. Among the pyrenes tested, 1,3,6,8-tetraethylpyrene showed the highest fluorescence quantum yield of 0.88 in the solid state.

Alkylation Reactions of Azodicarboxylate Esters with 4-Alkyl-1,4-Dihydropyridines under Catalyst-Free Conditions.

Introduction of alkyl groups on azodicarboxylate esters is an important method to prepare alkyl amine derivatives. Herein, we report reactions of 4-alkyl-1,4-dihydropyridines as alkylation reagents with di- tert-butyl azodicarboxylate to prepare alkyl amine derivatives under heating conditions. The alkylation reactions via C-C bond cleavage of the dihydropyridines are achieved in the absence of catalysts and additives.

Design, synthesis and molecular modeling studies on novel moxifloxacin derivatives as potential antibacterial and antituberculosis agents

Twenty-one novel alkyl/acyl/sulfonyl substituted fluoroquinolone derivatives were designed, synthesized and evaluated for their anti-tuberculosis and antibacterial activity. The targeted compounds were synthesized by the introduction of alkyl, acyl or sulfonyl moieties to the basic secondary amine moiety of moxifloxacin. Structures of the compounds were enlightened by FT-IR, 1H NMR, 13C NMR and HRMS data besides elemental analysis. Compounds were initially tested in vitro for their anti-mycobacterial activity against Mycobacterium tuberculosis H37Rv using microplate alamar blue assay. Minimal inhibitory concentration (MIC) values of all compounds were found between > 25.00–0.39 µg/mL while compounds 1, 2 and 13 revealed an outstanding activity against M. tuberculosis H37Rv with MIC values of 0.39 µg/mL. Activities of compounds 1–21 against to a number of Gram-positive and Gram-negative bacteria and fast growing mycobacterium strain were also investigated by agar well diffusion and microdilution methods. According to antimicrobial activity results, compound 13 was found the most potent derivative with a IC50 value of <1.23 μg/mL against Staphylococcus aureus and clinical strain of methicillin-resistant clinical strain of S. aureus.

Quaternary Phosphorus‐Induced Iodocuprate(I)‐Based Hybrids: Water Stabilities, Tunable Luminescence and Photocurrent Responses

Four (triphenyl)phosphonium‐based quaternary phosphorus salts with different substituents (varying from methyl to n‐butyl) were selected to be structural directed agents (SDAs) to construct four iodocuprate(I) hybrids via solution method, i.e., [(PPh3Me)(Cu3I4)]n (1), [(PPh3Et)(Cu3I4)]n (2), (PPh3iPr)2(Cu2I4) (3), [(PPh3nBu)(Cu3I4)]n (4). The inorganic iodocuprates in 1, 2 and 4 are 1‐D (Cu3I4)nn– chains constructed from Cu5I11 units, but (Cu2I4)2– in 3 is a di‐nuclear cluster. Interestingly, the strength of Cu···Cu and π–π stacking interactions are weakened with the lengthening of alkyl groups on P‐atom. The best water stability of 4 can be ascribed to the better hydrophobicity of n‐butyl group, which deters the dispersing of organic and inorganic moieties and as a result, inhibit hydrolysis reaction. Furthermore, all compounds exhibit typical reversible luminescent thermochromic behaviors, among which 4 exhibits blue emission and the quenching of higher energy (HE) zone in 1 and 2 are led by strong π–π stacking interactions. Besides, effective and repeatable photocurrent responses can be detected in these compounds. In all, by systematically introducing alkyl groups into (triphenyl)phosphonium as SDAs to prepare hybrid iodocuprates, we can find that the longer alkyl groups can achieve stronger tunable PL materials with enhanced water stabilities.

Total Synthesis of (-)-Xylogranatopyridine B via a Palladium-Catalyzed Oxidative Stannylation of Enones.

We report a total synthesis of the pyridine-containing limonoid alkaloid (-)-xylogranatopyridine B in 11 steps from commercially available dihydrocarvone. The central pyridine ring was assembled by a late-stage fragment coupling approach employing a modified Liebeskind pyridine synthesis. One fragment was prepared by an allyl-palladium catalyzed oxidative enone β-stannylation, in which the key bimetallic β-stannyl palladium enolate intermediate undergoes a β-hydride elimination. This methodology also allowed introduction of alkyl and silyl groups to the β-position of enones.

Novel amino-containing fluorene-based bisphthalonitrile compounds with flexible group

A series of amino-containing fluorene-based bisphthalonitrile (AFPN) monomers with alkyl or alkoxy groups were successfully produced by the reaction of 4-nitrophthalonitrile with 9, 9-bis (3-alkyl (or alkoxy)-4-aminophenyl)-2, 7-dihydroxylfluorene in the presence of potassium carbonate by a nucleophilic substitution reaction. The chemical structures of the synthesized monomers were confirmed by the Fourier transform infrared (FTIR), proton nuclear magnetic resonance, and carbon-13 nuclear magnetic resonance analyses. The synthesized monomers’ curing behaviors were evaluated by FTIR and differential scanning calorimetry, and a rheological analysis was performed to evaluate their respective processabilities. Moreover, dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) were performed for the thermomechanical, thermal, and thermo-oxidative analyses of the polymers. The results confirmed that the newly prepared phthalonitrile (PN) monomers with alkyl or alkoxy groups exhibited a self-promoted curing behavior. The rheological analysis suggested that the processing windows of the synthesized monomers were wider than that of APFN monomer bearing no flexible group. DMA and TGA revealed that the cured polymers exhibited high glass transition temperature (358–416°C) and the char yields at 800°C under nitrogen were between 70% and 77%. Moreover, the introduction of alkyl or alkoxy groups into the PN monomers’ backbones slightly reduced the thermal stability of the resulting polymers.