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Other Modification Processes
Published in Dick Sandberg, Andreja Kutnar, Olov Karlsson, Dennis Jones, Wood Modification Technologies, 2021
Dick Sandberg, Andreja Kutnar, Olov Karlsson, Dennis Jones
Wood components have a range of accessible hydroxyl groups, which can be modified by, for example, esterification with acetylation (see Section 2.2), but many modification processes involve the use of highly acidic or basic conditions or lead to by-products, so there is a need to develop treatments as close to pH-neutral as possible. In the early 1970s, Teyssié and Hubert considered the use of rhodium (II) acetate, while Paulissen et al. (1973) reported that a carbenoid group readily undergoes O-H insertion reactions with alcohols and water to yield alkoxyacetates in high yields (Figure 5.25).
Microwave-assisted reactions of α-diazoketones with hetaryl and ferrocenyl thioketones*
Published in Journal of Sulfur Chemistry, 2018
Grzegorz Mlostoń, Róża Hamera-Fałdyga, Małgorzata Jeske, Magdalena Godziszewska, Katarzyna Urbaniak, Heinz Heimgartner
α-Diazoketones form an important class of propargyl-allenyl-type 1,3-dipoles [7,8], which are widely explored in the [3+2]-cycloaddition chemistry. Moreover, they are known as important precursors of carbenes and carbenoids generated photolytically or by treatment with metal salts, for example, rhodium(II) acetate [9]. The presence of an electron-withdrawing acyl group reduces the 1,3-dipolar reactivity and their [3+2]-cycloadditions require harsher reaction conditions, or Lewis acids are applied as catalyst [10]. In recent years, microwave (MW)-supported reactions have extensively been elaborated, and in many cases drastic reduction of reaction times and improvement of yields of products were reported also for [3+2]-cycloadditions performed with diverse 1,3-dipoles [11,12].
Activity and selectivity of noble metal decorated nitrogen-doped carbon nanotubes supported on zeolite spheres in catalytic hydrogenation of benzophenone
Published in Journal of Dispersion Science and Technology, 2021
Ádám Prekob, Viktória Hajdu, László Vanyorek, Gábor Muránszky, Zsolt Fejes
The N-BCNT coated zeolite beads, as catalyst supports were synthetized based on our early work.[18] For catalyst synthesis anhydrous palladium(II) acetate, (Fluorochem Ltd.), rhodium(II) acetate dimer (Sigma-Aldrich) and dihydrogen chloroplatinic acid (Reanal) were used.