Solvent effects on the reactivity of solvated electrons with in C1 to C4 alcohols

1995 ◽  
Vol 73 (2) ◽  
pp. 284-288 ◽  
Author(s):  
Yixing Zhao ◽  
Gordon R. Freeman
Keyword(s):  
Solvent Effects ◽  
Trap Depth ◽  
Secondary Alcohols ◽  
Primary Alcohols ◽  
Solvated Electron ◽  
Solvated Electrons ◽  
Coulombic Repulsion ◽  
Keywords Alcohol ◽  
Alcohol Solvents ◽  
Effective Reaction

The rate constants [Formula: see text] in pure C1 to C4 alcohol solvents at 298 K increase with increasing viscosity and decreasing permittivity. Thus the reactivity increases with decreasing diffusivity and increasing coulombic repulsion, so the Debye–Smoluchowski model does not apply. The effective reaction radius κRr increases with decrease of effective trap depth Er/τ of the electrons in the solvent: κRr = CτRr(Er/τ)pτ. Values of κRr and Er/τ change with temperature, and values of Pτ fall in four categories: ∼0.0 for water and methanol; ∼1.3 for primary alcohols; 0.6 for secondary alcohols; 1.8 for tert-butanol. The C—H groups participate in the [Formula: see text] reaction. Keywords: alcohol solvents, solvated electron, nitrate ion, reactivity, solvent effects.

Solvent effects on the reactivity of solvated electrons with ammonium and nitrate ions in 1-butanol–water solvents

1993 ◽  
Vol 71 (9) ◽  
pp. 1303-1310 ◽  
Author(s):  
Ruzhong Chen ◽  
Gordon R. Freeman
Keyword(s):  
Solvent Effects ◽  
Pure Water ◽  
Reaction Rates ◽  
Dielectric Relaxation Time ◽  
Unusual Behavior ◽  
Solvated Electrons ◽  
Water Solvent ◽  
Electrical Conductances ◽  
Average Size ◽  
Effective Reaction

Values of the rate constants, k2 (106 m3 mol−1 s−1), of solvated electrons,[Formula: see text] with several related salts, in pure water and pure 1-butanol solvents at 298 K are, respectively, as follows: LiNO3, 9.2, 0.19; NH4NO3, 10, 8.3; NH4ClO4, 1.5 × 10−3, 12 in 20 mol% water; LiClO4, 1.0 × 10−4, < 1.0 × 10−4. The value of [Formula: see text] in water solvent is 48 times larger than that in 1-butanol solvent, whereas [Formula: see text] in water is 10−4 times smaller than the value in 1-butanol. This enormous reversal of solvent effects on [Formula: see text] reaction rates is the first observed for ionic reactants. The solvent participates chemically in the [Formula: see text] reaction, and the overall rate constant increases with increasing viscosity and dielectric relaxation time. This unusual behavior is attributed to a greatly increased probability of reaction of an encounter pair with increasing duration of the encounter. Effective reaction radii κRr for [Formula: see text] and [Formula: see text] were estimated with the aid of measured electrical conductances of the salt solutions in all the solvents. Values of κRr are (2–7) × 10−10 m, except for NH4,s+ in 100 and 99 mol% water, which are 2.6 and 2.7 × 10−14 m, respectively. The effective radii of the ions for mutual diffusion increase with increasing butanol content of the solvent, from ~50 pm in water to ~150 pm in 1-butanol, due to the increasing average size of the molecules that solvate the ions.

Solvent effects on the reactivity of solvated electrons with ions in tert-butanol/water mixtures

1995 ◽  
Vol 73 (3) ◽  
pp. 392-400 ◽  
Author(s):  
Yixing Zhao ◽  
Gordon R. Freeman
Keyword(s):  
Solvent Effects ◽  
Pure Water ◽  
Solvated Electrons ◽  
Rich Region ◽  
Tert Butanol ◽  
Einstein Model ◽  
Activation Energy For Diffusion ◽  
Minimum Number ◽  
Solvent Molecules ◽  
Effective Reaction

Reactions of [Formula: see text] with the ions [Formula: see text] showed different variations of rate with solvent composition in tert-butanol/water mixtures from 0 to 100 mol% water. In pure tert-butanol solvent at 298 K the respective values of k2 (106 m3 mol−1 s−1) are 3.2, 13, and 42. The estimated value of reaction radius Rr depends on the minimum number of solvent molecules needed between [Formula: see text] and the reactant ion to attain the static values of ε of the bulk solvent used in the calculation of the Debye factor f; Rr is assumed to be larger in the alcohol-rich region than in the water-rich region, because the solvent molecules are larger. The Smoluchowski–Debye–Nernst–Einstein model is used to evaluate the effective reaction radius κRr, where κ is the probability of reaction per encounter; κRr decreases from pure tert-butanol to pure water. In the water-rich region the activation energies E2 of the efficient reactions, 11–24 kJ mol−1, are similar to EΛ0 of the reactant electrolyes, 12–23 kJ mol−1. For the inefficient reactant [Formula: see text] E2 = 30 kJ mol−1. The high values of E2 = 43–53 kJ mol−1 in pure tert-butanol solvent are attributed to a high activation energy for diffusion of [Formula: see text] in this solvent. Keywords:tert-butanol/water solvents, solvated electron, ions, reactivity, solvent effects.

Article

1998 ◽  
Vol 76 (4) ◽  
pp. 411-413
Author(s):  
Yixing Zhao ◽  
Gordon R Freeman
Keyword(s):  
Absorption Spectrum ◽  
Optical Absorption ◽  
Temperature Dependence ◽  
Optical Absorption Spectrum ◽  
Infrared Light ◽  
Solvated Electron ◽  
Solvated Electrons ◽  
Tert Butanol ◽  
Solvent Dependence ◽  
Increasing Temperature

The energy and asymmetry of the optical absorption spectrum of solvated electrons, es- , change in a nonlinear fashion on changing the solvent through the series HOH, CH3OH, CH3CH3OH, (CH3)2CHOH, (CH3)3COH. The ultimate, quantum-statistical mechanical, interpretation of solvated electron spectra is needed to describe the solvent dependence. The previously reported optical spectrum of es- in tert-butanol was somewhat inaccurate, due to a small amount of water in the alcohol and to limitations of the infrared light detector. The present note records the remeasured spectrum and its temperature dependence. The value of the energy at the absorption maximum (EAmax) is 155 zJ (0.97 eV) at 299 K and 112 zJ (0.70 eV) at 338 K; the corresponding values of G epsilon max (10-22 m2 aJ-1) are 1.06 and 0.74. These unusually large changes are attributed to the abnormally rapid decrease of dielectric permittivity of tert-butanol with increasing temperature. The band asymmetry at 299 K is Wb/Wr = 1.8.Key words: optical absorption spectrum, solvated electron, solvent effects, tert-butanol, temperature dependence.

Revisiting Sodium Hypochlorite Pentahydrate (NaOCl·5H2O) for the Oxidation of Alcohols in Acetonitrile without Nitroxyl Radicals

Synlett ◽  
2018 ◽  
Vol 29 (18) ◽  
pp. 2404-2407 ◽  
Author(s):  
Tsunehisa Hirashita ◽  
Yuto Sugihara ◽  
Shota Ishikawa ◽  
Yohei Naito ◽  
Yuta Matsukawa ◽  
...  
Keyword(s):  
Sodium Hypochlorite ◽  
Nitroxyl Radicals ◽  
Secondary Alcohols ◽  
Primary Alcohols ◽  
Oxidation Of Alcohols

Sodium hypochlorite pentahydrate (NaOCl·5H2O) is capable of oxidizing alcohols in acetonitrile at 20 °C without the use of catalysts. The oxidation is selective to allylic, benzylic, and secondary alcohols. ­Aliphatic primary alcohols are not oxidized.

Ruthenium Pincer-Catalyzed Cross-Dehydrogenative Coupling of Primary Alcohols with Secondary Alcohols under Neutral Conditions

2012 ◽  
Vol 354 (13) ◽  
pp. 2403-2406 ◽  
Author(s):  
Dipankar Srimani ◽  
Ekambaram Balaraman ◽  
Boopathy Gnanaprakasam ◽  
Yehoshoa Ben-David ◽  
David Milstein
Keyword(s):  
Secondary Alcohols ◽  
Primary Alcohols ◽  
Dehydrogenative Coupling ◽  
Neutral Conditions

scholarly journals Construction of a (NNN)Ru-Incorporated Porous Organic Polymer with High Catalytic Activity for β-Alkylation of Secondary Alcohols with Primary Alcohols

Polymers ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 231
Author(s):  
Yao Cui ◽  
Jixian Wang ◽  
Lei Yu ◽  
Ying Xu ◽  
David J. Young ◽  
...  
Keyword(s):  
Functional Group ◽  
Catalytic Efficiency ◽  
Organic Polymer ◽  
Pincer Ligands ◽  
High Catalytic Activity ◽  
Secondary Alcohols ◽  
Primary Alcohols ◽  
Solid Supports ◽  
Porous Organic Polymer ◽  
Heterogeneous And Homogeneous Catalysis

Solid supports functionalized with molecular metal catalysts combine many of the advantages of heterogeneous and homogeneous catalysis. A (NNN)Ru-incorporated porous organic polymer (POP-bp/bbpRuCl3) exhibited high catalytic efficiency and broad functional group tolerance in the C–C cross-coupling of secondary and primary alcohols to give β-alkylated secondary alcohols. This catalyst demonstrated excellent durability during successive recycling without leaching of Ru which is ascribed to the strong binding of the pincer ligands to the metal ions.

Aerobic oxidation of primary alcohols in the presence of activated secondary alcohols

2005 ◽  
Vol 46 (5) ◽  
pp. 783-786 ◽  
Author(s):  
Hiromichi Egami ◽  
Hideki Shimizu ◽  
Tsutomu Katsuki
Keyword(s):  
Aerobic Oxidation ◽  
Secondary Alcohols ◽  
Primary Alcohols

One Pot Tandem Dual C=C and C=O Bond Reductions in β-Alkylation of Secondary Alcohols with Primary Alcohols by Ruthenium Complexes of Amido and Picolyl Functionalized N-Heterocyclic Carbenes

2021 ◽  
Author(s):  
A. P. Prakasham ◽  
Sabyasachi Ta ◽  
Shreyata Dey ◽  
Prasenjit Ghosh
Keyword(s):  
Ruthenium Complexes ◽  
Heterocyclic Carbenes ◽  
Secondary Alcohols ◽  
Coupling Reactions ◽  
Primary Alcohols ◽  
One Pot ◽  
The One ◽  
Alcohol Alcohol

Two different class of ruthenium complexes, namely, [1-mesityl-3-(2,6-Me2-phenylacetamido)-imidazol-2-ylidene]Ru(p-cymene)Cl (1c) and {[1-(pyridin-2-ylmethyl)-3-(2,6-Me2-phenyl)-imidazol-2-ylidene]Ru(p-cymene)Cl}Cl (2c), successfully carried out the one-pot tandem alcohol-alcohol coupling reactions of a variety of secondary and primary alcohols, in...

Iridium-Catalyzed Alkylation of Secondary Alcohols with Primary Alcohols: A Route to Access Branched Ketones and Alcohols

2020 ◽  
Vol 85 (14) ◽  
pp. 9139-9152 ◽  
Author(s):  
Sertaç Genç ◽  
Süleyman Gülcemal ◽  
Salih Günnaz ◽  
Bekir Çetinkaya ◽  
Derya Gülcemal
Keyword(s):  
Secondary Alcohols ◽  
Primary Alcohols
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