Thermal isomerization of quadricyclane to norbornadiene catalyzed by copper(II) and tin(II) salts

Fife, Dennis J.; Morse, Karen W.; Moore, William M.

doi:10.1021/ja00363a032

Cited by 20 publications

(45 citation statements)

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“…[21][22][23] Moore and co-workers suggested that both one-site and twosite coordination of quadricyclane, with rate constants 2.9 × 10 -2 min -1 g -1 and 7.3 × 10 -2 min -1 g -2 , respectively, for the CuSO 4 catalyst in benzene, may lead to the production of norbornadiene. 13 In our previous work, 16 if a one-site coordinated reaction was assumed to dominate, then our result of 2.7 × 10 -2 min -1 g -1 was consistent with that obtained above in a stirred solution. 13 Nevertheless, if the contribution of two-site coordination was included, our one-site coordinated rate constant became smaller.…”

Section: Introductionsupporting

confidence: 92%

“…13 In our previous work, 16 if a one-site coordinated reaction was assumed to dominate, then our result of 2.7 × 10 -2 min -1 g -1 was consistent with that obtained above in a stirred solution. 13 Nevertheless, if the contribution of two-site coordination was included, our one-site coordinated rate constant became smaller. In another similar experiment with Raman spectroscopy, Vickers and co-workers obtained a consistent second-order depletion rate constant of 2.7 × 10 -2 min -1 g -1 for quadricyclane with CuSO 4 as the catalyst, but they did not look into the reaction mechanism.…”

Section: Introductionsupporting

confidence: 92%

“…In a similar experiment, Moore and co-workers have obtained the one-site and two-site coordinated rate constants to be 4.8 × 10 -4 s -1 g -1 and 1.2 × 10 -3 s -1 g -2 , respectively, for the CuSO 4 catalyst in benzene by detection with GC-MS. Given, in eq 2, the particle diameter of 3.3 × 10 -3 cm and a total volume of 10 mL in a stirred solution to substitute for the effective solvent volume, 13 then their conditions may lead to the corresponding values of 9.6 × 10 -6 s -1 A -1 and 4.7 × 10 -7 s -1 A -2 , in comparison with our results (8.5 ( 5.9) × 10 -6 s -1 A -1 and (2.2 ( 0.8) × 10 -8 s -1 A -2 at 27 °C. The one-site rate constants are consistent with each other, but the two-site rate constants differ by 20 times.…”

Section: A Determination Of Kinetic Constants In Solution Withoutmentioning

confidence: 99%

“…In the catalytic conversion reaction, Moore and co-workers determined the quadricyclane and norbornadiene concentrations by gas chromatography. 13 Their procedure requires the removal and analysis of aliquots of the reaction mixture at intervals during the reaction. To develop an in situ monitoring of the concentration variation for both substances, Vickers and co-workers demonstrated with fiberoptic Raman spectroscopy the potential for automated, nondestructive, and continuous probing of the isomerization.…”

Section: Introductionmentioning

confidence: 99%

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Catalytic Isomerization of Quadricyclane Using Fourier Transform Near-Infrared Absorption Spectroscopy: Diffusion, Conversion, and Temperature Effect

et al. 2006

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By using Fourier transform near-infrared (NIR) absorption spectroscopy, the kinetic behaviors of quadricyclane isomerization, as catalyzed by anhydrous CuSO(4) in chloroform mixture with and without agitation, are presented. Given the acquired NIR spectra, the concentration decay of quadricyclane with the reaction time is determined with the aid of partial least-squares analysis. When the mixture is not agitated, the diffusion coefficients in chloroform are evaluated to be (3.8 +/- 0.1) x 10(-5) cm(2) s(-1) at 27 degrees C and (4.4 +/- 0.1) x 10(-5) cm(2) s(-1) at 39 degrees C. In the size-dependent experiments of the catalyst, the one-site and two-site coordinated conversion rate constants are further determined to be (8.5 +/- 5.9) x 10(-6) s(-1) A(-1) and (2.2 +/- 0.8) x 10(-8) s(-1) A(-2), respectively, at 27 degrees C and (1.3 +/- 0.8) x 10(-5) s(-1) A(-1) and (1.92 +/- 0.01) x 10(-6) s(-1) A(-2), respectively, at 39 degrees C. A denotes the total catalyst surface area per unit effective volume of solvent. Accordingly, the activation energies for one-site and two-site coordination are evaluated to be 24.8 and 286.2 kJ mol(-1), respectively. The reaction is dominated by one-site coordination (1:1 complex) between the reactant and the catalyst. Unless temperature increases, the two-site coordinated reaction may be ignored. In contrast, when analogous experiments are performed in the stirred solution, the diffusion factor is ignored but the conversion rate constants rise due to the increase of collision frequency. For instance, the one-site and two-site coordinated rate constants are increased to (1.7 +/- 1.4) x 10(-5) s(-1) A(-1) and (1.27 +/- 0.06) x 10(-5) s(-1) A(-2) at 39 degrees C. The two-site coordinated reaction rate is enhanced by a factor of 10. Thus, isomerization may proceed via both 1:1 and 1:2 coordination between the reactant and the catalyst. The Arrhenius plot yields the corresponding activation energies to be 24 +/- 3 and 275 +/- 3 kJ mol(-1). The activation energies remain constant, no matter whether the solution is agitated or not.

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Section: Introductionsupporting

confidence: 92%

Section: Introductionsupporting

confidence: 92%

Section: A Determination Of Kinetic Constants In Solution Withoutmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Catalytic Isomerization of Quadricyclane Using Fourier Transform Near-Infrared Absorption Spectroscopy: Diffusion, Conversion, and Temperature Effect

et al. 2006

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“…Thus, the anhydrous CuCl 2 in benzene catalysed the isomerization and the conversion of 193 to 194, the rate being dependent on the amount of salt in contact with the solution (Scheme 83). Mainly norbornadiene was produced in the catalytic process, but a side-product was also formed by the addition of chlorine or bromine to the quadricyclane [128]. Cu(II) salts of 1,3-dicarbonyl compounds, active methylene compounds 1 9 6 or anisole to give condensation or substitution products 197, accompanied by C-S bond cleavage (Scheme 84) [129].…”

Section: Other Copper(ii) Halide-mediated Reactionsmentioning

confidence: 99%

Versatile Reactivity and Catalytic Effects of Copper(II) Halides in Organic Syntheses

Csende¹,

Stájer

2005

COC

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Copper(II) salts are widely applied for the halogenation of aromatic and heteroaromatic systems, the halides. In coupling reactions, CuCl 2 has been used as a catalyst for the benzylation of aromates, the synthesis of alkanes, and the preparation of diacetylenes, cyclohexenones and symmetric biaryls. It has further proved suitable for stereoselective cyclization to lactones, carbon-nitrogen coupling and lactamization, and for the simple preparation of aroylaminohydrazones, the allylic amination of olefins, the carbonylation of alkylamines, and heterocyclizations to pyrrolidinones, pyridinones, pyrroles and dihydrofurans. The dehydrogenation of carbocycles and heterocycles can be used in the synthesis of gibberelic acid, for the aromatization of oestrogen derivatives and for the conversion of dihydrouracils to uracils. From tetrahydroisoquinolines, dihydro derivatives have been formed, while dihydropyridazines in the presence of Cu(II) salts yield pyridazines. Similarly, the oxidations of cyclohexane, adamantane and methylcatechol to benzoquinone, and amines to nitriles have been performed. The conversion of aldehydes to nitriles and benzyl radical cyclizations to butyrolactones have been achieved. Protection and deprotection, and various other Cu(II) halide-mediated reactions are also discussed.

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Solar Energy Storage by Molecular Norbornadiene–Quadricyclane Photoswitches: Polymer Film Devices

et al. 2019

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Devices that can capture and convert sunlight into stored chemical energy are attractive candidates for future energy technologies. A general challenge is to combine efficient solar energy capture with high energy densities and energy storage time into a processable composite for device application. Here, norbornadiene (NBD)–quadricyclane (QC) molecular photoswitches are embedded into polymer matrices, with possible applications in energy storing coatings. The NBD–QC photoswitches that are capable of absorbing sunlight with estimated solar energy storage efficiencies of up to 3.8% combined with attractive energy storage densities of up to 0.48 MJ kg −1 . The combination of donor and acceptor units leads to an improved solar spectrum match with an onset of absorption of up to 529 nm and a lifetime ( t 1/2 ) of up to 10 months. The NBD–QC systems with properties matched to a daily energy storage cycle are further investigated in the solid state by embedding the molecules into a series of polymer matrices revealing that polystyrene is the preferred choice of matrix. These polymer devices, which can absorb sunlight and over a daily cycle release the energy as heat, are investigated for their cyclability, showing multicycle reusability with limited degradation that might allow them to be applied as window laminates.

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Thermal isomerization of quadricyclane to norbornadiene catalyzed by copper(II) and tin(II) salts

Cited by 20 publications

References 0 publications

Catalytic Isomerization of Quadricyclane Using Fourier Transform Near-Infrared Absorption Spectroscopy: Diffusion, Conversion, and Temperature Effect

Catalytic Isomerization of Quadricyclane Using Fourier Transform Near-Infrared Absorption Spectroscopy: Diffusion, Conversion, and Temperature Effect

Versatile Reactivity and Catalytic Effects of Copper(II) Halides in Organic Syntheses

Solar Energy Storage by Molecular Norbornadiene–Quadricyclane Photoswitches: Polymer Film Devices

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