Photochromism of Asymmetrical Diarylethenes with a Pyrrole Unit: Effects of Aromatic Stabilization Energies of Aryl Rings

Four novel asymmetrical diarylethenes with a pyrrole and a variable aryl unit have been synthesized. Their crystal structures and photochromic performance were systematically studied to elucidate the effects of the aromatic stabilization energy (ASE) of aryl units. Experimental results showed that their thermal stability as well as cyclization quantum yield, photoconversion ratio, fluorescence modulation efficiency, and fatigue resistance exhibited a strong correlation with ASE

Photochromism of Asymmetrical Diarylethenes with a Pyrrole Unit: Effects of Aromatic Stabilization Energies of Aryl Rings

Four novel asymmetrical diarylethenes with a pyrrole and a variable aryl unit have been synthesized. Their crystal structures and photochromic performance were systematically studied to elucidate the effects of the aromatic stabilization energy (ASE) of aryl units. Experimental results showed that their thermal stability as well as cyclization quantum yield, photoconversion ratio, fluorescence modulation efficiency, and fatigue resistance exhibited a strong correlation with ASE

Photochromism of Asymmetrical Diarylethenes with a Pyrrole Unit: Effects of Aromatic Stabilization Energies of Aryl Rings

Four novel asymmetrical diarylethenes with a pyrrole and a variable aryl unit have been synthesized. Their crystal structures and photochromic performance were systematically studied to elucidate the effects of the aromatic stabilization energy (ASE) of aryl units. Experimental results showed that their thermal stability as well as cyclization quantum yield, photoconversion ratio, fluorescence modulation efficiency, and fatigue resistance exhibited a strong correlation with ASE

Photochromism of Asymmetrical Diarylethenes with a Pyrrole Unit: Effects of Aromatic Stabilization Energies of Aryl Rings

Four novel asymmetrical diarylethenes with a pyrrole and a variable aryl unit have been synthesized. Their crystal structures and photochromic performance were systematically studied to elucidate the effects of the aromatic stabilization energy (ASE) of aryl units. Experimental results showed that their thermal stability as well as cyclization quantum yield, photoconversion ratio, fluorescence modulation efficiency, and fatigue resistance exhibited a strong correlation with ASE

Synthesis of 2-(Polyfluoroaryl)benzofurans via a Copper(I)-Catalyzed Reaction of 2-(2,2-Dibromovinyl)phenol with Polyfluoroarene

A novel and efficient route for the synthesis of 2-(polyfluoroaryl)benzofurans via a copper(I)-catalyzed tandem reaction of 2-(2,2-dibromovinyl)phenol with polyfluoroarene is reported. The corresponding products are generated in good yields. During the reaction process, a copper-catalyzed intramolecular C–O bond formation and a C–H activation are involved

Primary sulfonamide as a coupling partner: Copper(I)-catalyzed regioselective cross-coupling of 2-nitro benzenesulfonamides with thiol through the cleavage of Ar–SO₂NH₂ bonds

<p>In this article, we have presented a novel and efficient method for the direct synthesis of unsymmetrical sulfides through the copper(I)-catalyzed cross-coupling of 2-nitro benzenesulfonamides with thiols in the presence of catalytic amount of CuI in DMF as solvent at 100 °C. In addition, the products were obtained in high to excellent yields. More importantly, the novel system showed the primary 2-nitro benzenesulfonamides as a new coupling partner and regioselectively promoted C–S bond-forming transformations through the cleavage of Ar–SO₂NH₂ bonds.</p

Copper-Catalyzed Diversity-Oriented Synthesis (DOS) of 4‑Amino‑2<i>H</i>‑chromen-2-imines: Application of Kemp Elimination toward O‑Heterocycles

We report herein a copper-catalyzed sequential multicomponent reaction of benzo­[<i>d</i>]­isoxazoles with terminal alkynes and sulfonyl azides, which produced divergent 4-amino-2<i>H</i>-chromen-2-imines with excellent chemical selectivity. The reaction tolerated a broad range of functional groups, and released only N₂ as the sole byproduct. The sulfonyl imino group could be removed to give biologically active free 4-amino-2<i>H</i>-chromenone in good yield

Multiaddressing Fluorescence Switch Based on a New Photochromic Diarylethene with a Triazole-Linked Rhodamine B Unit

A novel diarylethene with a triazole-linked rhodamine B unit has been synthesized by click chemistry. When triggered by light, proton, and metal ions, the diarylethene can be used as a fluorescence switch, leading to a multiaddressable system. The diarylethene shows sequence-dependent responses through efficient interaction of the specific triazole-linked rhodamine B unit with proton and metal ions. Furthermore, the diarylethene can serve as a naked-eye chemosensor for highly selective recognition of different metal ions in different solvent systems. The diarylethene was highly selective toward Al³⁺ with remarkable fluorescence change from dark to yellow in acetonitrile, while it selectively recognized Cu²⁺ with significant fluorescence change from dark to bright yellow in the mixture of acetonitrile and water (v/v = 4/6). Finally, a logic circuit was constructed with the unimolecular platform by using the combinational stimuli of light and chemical species as inputs and the fluorescence intensity at 595 nm as output