543-75-9Relevant articles and documents
Lignol cleavage by Pd/C under mild conditions and without hydrogen: A role for benzylic C=H activation?
Zhou, Xiaoyuan,Mitra, Joyee,Rauchfuss, Thomas B.
, p. 1623 - 1626 (2014/07/08)
The cleavage of C=O bonds in lignin model compounds without hydrogen was developed using the commercially available Pd/C. Hydrogen donor solvents are helpful for this reaction through transfer hydrogenation, but not necessary. A redox neutral process that utilizes the internal hydrogen source for the cleavage is also possible. An initial mechanistic study indicates that the β-benzylic-H atom in the substrate plays a critical role and that the present system undergoes a process different from previous reports. Cleavage within: The selective cleavage of β-O-4 bond linkage in lignin has received great attention. We developed a method using the commercially available heterogeneous catalyst, Pd/C, to cleave the C=O bond in β-O-4 linkage model compound without hydrogen. A mechanistic study shows that the present catalytic system undergoes a process different from previous reports, in which the β-benzylic-H atom in the substrates plays a critical role.
Synthesis of 1,4-dioxene from diethylene glycol in the presence of bifunctional copper-containing catalysts. Effect of support on the selectivity of dioxene formation
Gitis,Neumoeva,Isagulyants
, p. 23 - 29 (2007/10/03)
In the synthesis of 1,4-dioxene from diethylene glycol in the presence of a bifunctional copper-containing catalyst, the composition of the by-products has been studied and the effect of the support on the overall direction of the reactions has been investigated. It has been established that on Cu/SiO2, 1,4-dioxanone is formed together with dioxene, the yield of the former increasing with an increase in the content of copper in the catalyst. This is due to an increase in the dehydrogenating function of the latter. On the more acidic Cu/Al2O3, 1,4-dioxane is mainly obtained together with, to a lesser degree, methyl-1,3-dioxolane. This is due to the predominance of dehydration reactions followed by isomerization. Dioxene, dioxane, and methyldioxolane are formed on Cu/HNaY, and the yield of the latter increases with an increase in the degree of acidity (degree of decationization) of the zeolite. It is possible to increase the selectivity of dioxene formation substantially with the use of a catalyst with a moderately acidic zeolite, by varying its copper content and by dilution with water vapor. 1996 Plenum Publishing Corporation.