ISSN:
1432-5225
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Summary Three lignin model dimers of the phenacyl α-aryl ether type were treated with alkaline hydrogen peroxide under simulated technical bleaching conditions in the presence and absence of peroxide stabilization agents. The reaction products were characterized and their yields determined using a combination of gas chromatography and gas chromatography-mass spectrometry. The principal reaction in each case consisted in the displacement of the side chain via the Dakin reaction. In the case of one of the dimers, α-guaiacoxy-β-hydroxypropioguaiacone, a competing dehydration reaction occurred, resulting in the formation of guaiacyl α-guaiacoxyvinyl ketone, which subsequently was degraded to guaiacol and glycolic acid. Stabilization of the peroxide with Na5DTPA enhanced the yield of acyclic Dakin products (α-guaiacoxy carboxylic acids). Product analysis supported the conclusion that oxygen, formed from the decomposition of peroxide, was itself relatively unreactive in the initial phase of the reaction under peroxide bleaching conditions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00366502
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