Synthesis, structure and photophysical properties of dibenzofuran-fused boron dipyrromethenes

Regioselective functionalization of core per-substituted boron dipyrromethenes (BODIPYs) has been achieved efficiently based on tetrabromoBODIPY, which affords a series of dibenzofuran-fused chromophores, via a regioselective nucleophilic substitution reaction followed by direct palladium-catalyzed two-fold intramolecular ring fusion. These rigid dibenzofuran-fused BODIPYs showed impressive photophysical properties such as clearly red-shifted absorption and emission bands, enhanced absorption coefficients upon and intense fluorescence (close to unity).

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ESIPT on/off switching and crystallization-enhance emission properties of new design phenol-pyrazole modified cyclotriphosphazenes

New Journal of Chemistry ◽

10.1039/d1nj00894c ◽

2021 ◽

Author(s):

Ceylan Mutlu Balcı ◽

Süreyya Oğuz Tümay ◽

Serap Beşli

Keyword(s):

Nucleophilic Substitution ◽

Substitution Reaction ◽

Photophysical Properties ◽

Nucleophilic Substitution Reaction ◽

Emission Properties

Nucleophilic substitution reaction of [N3P3Cl2[(2,2′-dioxybiphenyl)2] (1) with 2-(1H-Pyrazol-3-yl) phenol (2) was performed in order to synthesize molecules that may exhibit different photophysical properties on the cyclotriphosphazene scaffold. Bis-geminal phenol-pyrazole (3)...

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Synthesis of Carbohydrate Based Macrolactones and Their Applications as Receptors for Ion Recognition and Catalysis

Molecules ◽

10.3390/molecules26113394 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3394

Author(s):

Surya B. Adhikari ◽

Anji Chen ◽

Guijun Wang

Keyword(s):

Nucleophilic Substitution ◽

Supramolecular Chemistry ◽

Copper Sulfate ◽

Substitution Reaction ◽

Biological Properties ◽

Anion Binding ◽

Nucleophilic Substitution Reaction ◽

Binding Properties ◽

Intramolecular Nucleophilic Substitution ◽

Leaving Groups

Glycomacrolactones exhibit many interesting biological properties, and they are also important in molecular recognitions and for supramolecular chemistry. Therefore, it is important to be able to access glycomacrocycles with different sizes and functionality. A new series of carbohydrate-based macrocycles containing triazole and lactone moieties have been designed and synthesized. The synthesis features an intramolecular nucleophilic substitution reaction for the macrocyclization step. In this article, the effect of some common sulfonate leaving groups is evaluated for macrolactonization. Using tosylate gave good selectivity for monolactonization products with good yields. Fourteen different macrocycles have been synthesized and characterized, of which eleven macrocycles are from cyclization of the C1 to C6 positions of N-acetyl D-glucosamine derivatives and three others from C2 to C6 cyclization of functionalized D-glucosamine derivatives. These novel macrolactones have unique structures and demonstrate interesting anion binding properties, especially for chloride. The macrocycles containing two triazoles form complexes with copper sulfate, and they are effective ligands for copper sulfate mediated azide-alkyne cycloaddition reactions (CuAAC). In addition, several macrocycles show some selectivity for different alkynes.

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Regioselective Oxidative Cross-Coupling Reaction: Synthesis of Imidazo[1,2-a]pyridine Fluorophores

Synthesis ◽

10.1055/s-0040-1706000 ◽

2021 ◽

Author(s):

Xianglong Chu ◽

Yadi Niu ◽

Chen Ma ◽

Xiaodong Wang ◽

Yunliang Lin ◽

...

Keyword(s):

Photophysical Properties ◽

Coupling Reaction ◽

Cross Coupling ◽

Quantum Yields ◽

Fluorescence Quantum Yields ◽

Cross Coupling Reaction ◽

Color Tunable ◽

Palladium Catalyzed ◽

Structure Relationship ◽

High Fluorescence

AbstractA rapid access to a series of N-heteroarene fluorophores has been developed on the basis of the palladium-catalyzed direct oxidative C–H/C–H coupling of imidazo[1,2-a]pyridines with thiophenes/furans. The photophysical properties–structure relationship was systematically investigated. The resulting N-heteroarene fluorophores present color-tunable emissions (λem: 431–507 nm in CH2Cl2) and high fluorescence quantum yields (up to 91% in CH2Cl2).

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