630-19-3Relevant articles and documents
Microwave Spectrum, Molecular Structure and Dipole Moment of Pivalaldehyde
Cox, Peter A.,Couch, Andrew D.,Hillig, Kurt W.,LaBarge, Marabeth S.,Kuczkowski, Robert L.
, p. 2689 - 2698 (1991)
The microwave spectra of eight isotopic species of pivalaldehyde have been studied in the frequency region 9-40 GHz.The zero-point average skeletal structure has been derived to be: r = 1.206(6) Angstroem, r = 1.130(5) Angstroem, r = 1.516(7) Angstroem, r = r = 1.537(2) Angstroem, C(1)C(2)C(3) = 110.5(4) deg, C(1)C(2)C(4),(5) = 107.4(3) deg, proj.C(4),(5)C(2)C(1) = 120.78(4) deg, CCO = 126.0(5) deg and CCH(1) = 113.0(3) deg.The tert-butyl group is found to be tilted 2 deg away from the C=O bond.Accurate Stark effect measurements have been performed on the main species, (CH3)3CCDO and (CD3)3CCHO.The ground-state dipole moment of (CH3)3CCHO was determined as μs = 2.618(5) D and μb = 0.728(2) D giving μtotal = 2.717(5) D at an angle of 13.6 deg to the C=O bond.
Kinetics and correlation analysis of reactivity in the oxidation of aliphatic primary alcohols by isoquinolinium dichromate in non-aqueous medium
Kalal, Reena,Panday, Dinesh
, (2021/06/28)
Mild oxidation in dimethyl sulfoxide (DMSO) medium by isoquinolinium dichromate (IQDC) of aliphatic primary alcohols produces corresponding carbonyl compounds. A Michaelis-Menten kind kinetics noticed as for alcohols while unit dependency on rate observed as for IQDC. At non-identical temperatures the formation constants and the rates of decomposition of alcohol-IQDC complexes have been evaluated. Thermodynamic parameters and activation parameters for formation of the complex and break down of the complexes have been determined respectively. The oxidation process accelerates with increase in proton concentration. An α-C-H bond fisson in the rate-controlling step suggested by the deuterium isotope effect. For oxidation of ethanol, kH/kD = 5.82 at 293 K, was observed. The oxidation rates have been evaluated in 19 organic solvents and greater role of solvating power of the cation is observed. Depended on the kinetic parameters, solvent effect analysis and the outcome of thermodynamic parameters, a mechanism in which rate-controlling break down of the complex is suggested, to give the resulting product through hydride-ion transfer with a cyclic transition state.
Solvent-free, microwave assisted oxidation of alcohols with 4-hydroxypyridinium chlorochromate functionalized silica gel
AHMADI, Sayed Ali,GHALEHBANDI, Shermineh Sadat,GHAZANFARI, Dadkhoda,SHEIKHHOSSEINI, Enayatollah
, p. 283 - 289 (2020/10/06)
4-Hydroxypyridinium chlorochromate functionalized silica gel was found to be an efficient and reusable oxidant for the very fast oxidation of primary and secondary alcohols to the corresponding carbonyl compounds under solventfree conditions and microwave irradiation in excellent yields.