Esters of 2,5-multisubstituted-1,3-dioxane-2-carboxylic acid: their conformational analysis and selective hydrolysis

Harabe, Tetsuji; Matsumoto, Takatoshi; Shioiri, Takayuki

doi:10.1016/j.tet.2009.02.076

Cited by 7 publications

(5 citation statements)

References 28 publications

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“…The more stable endo than exo isomer in Me 2 SAF 6 is understood to be subject to the electron-withdrawing nature of C 60 that stabilizes a hybridized molecular orbital comprising the lone pair of the oxygen atom and σ* orbital of the closest C–C bond (Supporting Information Figure S11). This is analogous to, but not exactly the same as, the anomeric effect that is well documented for pyran and dioxane. − …”

Section: Resultssupporting

confidence: 55%

Stereochemistry of Spiro-Acetalized [60]Fullerenes: How the Exo and Endo Stereoisomers Influence Organic Solar Cell Performance

Mikie

Saeki

Yamazaki

et al. 2015

ACS Appl. Mater. Interfaces

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Exploiting bis-addition products of fullerenes is a rational way to improve the efficiency of bulk heterojunction-type organic photovoltaic cells (OPV); however, this design inherently produces regio- and stereoisomers that may impair the ultimate performance and fabrication reproducibility. Here, we report unprecedented exo and endo stereoisomers of the spiro-acetalized [60]fullerene monoadduct with methyl- or phenyl-substituted 1,3-dioxane (SAF6). Although there is no chiral carbon in either the reagent or the fullerene, equatorial (eq) rather than axial (ax) isomers are selectively produced at an exo-eq:endo-eq ratio of approximately 1:1 and can be easily separated using silica gel column chromatography. Nuclear Overhauser effect measurements identified the conformations of the straight exo isomer and bent endo isomer. We discuss the origin of stereoselectivity, the anomeric effect, intermolecular ordering in the film state, and the performance of poly(3-hexylthiophene):substituted SAF6 OPV devices. Despite their identical optical and electrochemical properties, their solubilities and space-charge limited current mobilities are largely influenced by the stereoisomers, which leads to variation in the OPV efficiency. This study emphasizes the importance of fullerene stereochemistry for understanding the relationship between stereochemical structures and device output.

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Section: Resultssupporting

confidence: 55%

Stereochemistry of Spiro-Acetalized [60]Fullerenes: How the Exo and Endo Stereoisomers Influence Organic Solar Cell Performance

Mikie

Saeki

Yamazaki

et al. 2015

ACS Appl. Mater. Interfaces

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“…From the information listed in Table , it is possible to note that the main interaction is that established between the acidic hydrogen atom in the nucleophilic center and the o -NO 2 group in the substrate. − On the other hand, the homoanomeric effect − that may be present in the nucleophile is weaker than the interaction between the nucleophile and the electrophile. Nevertheless, the energy values observed are within the range previously reported .…”

Section: Resultsmentioning

confidence: 99%

Hydrogen Bond Contribution to Preferential Solvation in S_NAr Reactions

et al. 2013

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Preferential solvation in aromatic nucleophilic substitution reactions is discussed using a kinetic study complemented with quantum chemical calculations. The model system is the reaction of a series of secondary alicyclic amines toward phenyl 2,4,6-trinitrophenyl ether in aqueous ethanol mixtures of different compositions. From solvent effect studies, it is found that only piperidine is sensitive to solvation effects, a result that may be traced to the polarity of the solvent composition in the ethanol/water mixture, which points to a specific electrophilic solvation in the aqueous phase.

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“…The resulting diol was obtained without further purification in 95 % yield as a colorless oil (lit. reported compound26). 1 H NMR (300 MHz, CDCl 3 ): δ = 3.62–3.84 (m, 4 H, C H 2 OH), 2.27 (s, 2 H, OH), 1.68 (m, 1 H, CH), 1.32 (quint, J = 7.6 Hz, 2 H, C H 2 CH 3 ), 1.24 (t, J = 7.6 Hz, 3 H, CH 2 C H 3 ) ppm.…”

Section: Methodsmentioning

confidence: 99%

Combination of Carbon Nitride and Carbon Nanotubes: Synergistic Catalysts for Energy Conversion

et al. 2014

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Due to their versatile features and environmental friendliness, functionalized carbon materials show great potential in practical applications, especially in energy conversion. Developing carbon composites with properties that can be modulated by simply changing the ratio of the original materials is an intriguing synthetic strategy. Here, we took cyanamide and multiwalled carbon nanotubes as precursors and introduced a facile method to fabricate a series of graphitic carbon nitride/carbon nanotubes (g-C3 N4 /CNTs) composites. These composites demonstrated different practical applications with different weight ratios of the components, that is, they showed synergistic effects in optoelectronic conversion when g-C3 N4 was the main ingredient and in oxygen reduction reaction (ORR) when CNTs dominated the composites. Our experiments indicated that the high electrical conductivity of carbon nanotubes promoted the transmission of the charges in both cases.

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Esters of 2,5-multisubstituted-1,3-dioxane-2-carboxylic acid: their conformational analysis and selective hydrolysis

Cited by 7 publications

References 28 publications

Stereochemistry of Spiro-Acetalized [60]Fullerenes: How the Exo and Endo Stereoisomers Influence Organic Solar Cell Performance

Stereochemistry of Spiro-Acetalized [60]Fullerenes: How the Exo and Endo Stereoisomers Influence Organic Solar Cell Performance

Hydrogen Bond Contribution to Preferential Solvation in S_NAr Reactions

Combination of Carbon Nitride and Carbon Nanotubes: Synergistic Catalysts for Energy Conversion

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Esters of 2,5-multisubstituted-1,3-dioxane-2-carboxylic acid: their conformational analysis and selective hydrolysis

Cited by 7 publications

References 28 publications

Stereochemistry of Spiro-Acetalized [60]Fullerenes: How the Exo and Endo Stereoisomers Influence Organic Solar Cell Performance

Stereochemistry of Spiro-Acetalized [60]Fullerenes: How the Exo and Endo Stereoisomers Influence Organic Solar Cell Performance

Hydrogen Bond Contribution to Preferential Solvation in SNAr Reactions

Combination of Carbon Nitride and Carbon Nanotubes: Synergistic Catalysts for Energy Conversion

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Hydrogen Bond Contribution to Preferential Solvation in S_NAr Reactions