403-33-8Relevant articles and documents
Absolute raman intensities of the carbonyl stretching band in para substituted methyl benzoates
Vanderheyden,Zeegers-Huyskens
, p. 1423 - 1428 (1989)
The absolute Raman intensities of the vC=0 band of para-substituted methyl benzoates have been measured in CCl4 solution at different excitation frequencies. The intensities depend on a preresonance Raman effect (PRRE) and are correlated with theoretical expressions which describe the dispersion of the Raman intensity as a function of the excitation frequency and the experimental UV frequencies of the compounds, in particular the π→π* 1La band. The Raman intensities free from PRRE are deduced by extrapolating the experimental values to a zero excitation frequency. These extrapolated intensities depend on the electron-donating character of the substituents and on the extent of the conjugated system. The depolarization ratio of the vC=0 band in methyl benzoates increases with the excitation energies. This ratio is higher for the para-substituted derivatives.
The Highly Effective Cobalt Based Metal–Organic Frameworks Catalyst for One Pot Oxidative Esterification Under Mild Conditions
Chindawong, Chakkresit,Mekrattanachai, Pagasukon,Setthaya, Naruemon,Song, Wei Guo,Zhu, Lei
, (2021/08/03)
The cobalt-based metal organic frameworks (Co-MOFs) catalyst has been prepared with using terephthalic acid and 4,4′-bipyridine as organic linkers by facile solvothermal method for one pot oxidative esterification. The prepared catalyst was pyrolysed at different temperature and then applied for oxidation of aldehyde using molecular oxygen as benign oxidant under mild conditions. The Co-MOFs pyrolysed at 800?°C (denoted as Co-MOFs-800) catalyst exhibited excellent catalytic activity, selectivity and recyclability toward the oxidative esterification of benzaldehydes. Furthermore, it can be reused up to 5 runs without significant loss of activity. Graphic Abstract: [Figure not available: see fulltext.]
Hydroxyl radical-mediated oxidative cleavage of CC bonds and further esterification reaction by heterogeneous semiconductor photocatalysis
Hong, Mei,Jia, Rui,Miao, Hongyan,Ni, Bangqing,Niu, Tengfei,Wang, Hui
, p. 6591 - 6597 (2021/09/10)
A hydroxyl radical-mediated aerobic cleavage of alkenes and further sequence esterification reaction for the preparation of carbonyl compounds have been developed by using tubular carbon nitride (TCN) as a general heterogeneous photocatalyst under an oxygen atmosphere with visible light irradiation. This protocol has an excellent substrate scope and gives the desired aldehydes, ketones and esters in moderate to high yields. Importantly, this metal-free procedure employed photogenerated hydroxyl radicals in situ as green oxidation active species, avoiding the present additional initiators. The reaction could be carried out under solar light irradiation and was applicable to large-scale reactions. Furthermore, the recyclable TCN catalyst could be used several times without a significant loss of activities.