Vol. 65insoluble product not being obtained by re-ethanolysis of 3 mafile ether-soluble lignin.As in the case of maple lignin, the water-soluble spruce lignin (G') could be separated into a petroleum etherinsoluble (J') and a petroleum ether-soluble (K') fraction and the latter separated further into a bisulfite (L'), an acid (M'), an alkali (N') and a neutral (0') fraction.From the bisulfite and alkali fractions 1-(4-hydroxy-3methoxyphenyl)-1,2-propanedione and Z-ethoxy-l-(4-hydroxy-3-methoxyphenyl)-l-propanone, respectively, were isolated and identified by the usual methods.3 Thus re-ethanolysis of both spruce and maple ethanol lignin fractions yields the same products as isolated by use of the standard wood ethanolysis procedure and there would seem to be no doubt but that the extraction of lignin by the action of ethanolic hydrogen chloride involves the previously-discussed' concurrent polymerization-depolymerization changes. The amount of polymerization is evidently greater, and the depolymerization less, in spruce (a gymnosperm) than in maple (an angiospermi. The fact that l-(4-hydroxy-3-methoxyphenyl)-l,2-propanedione and 2-ethoxy-l-(4-hydroxy-3-methoxyphenyl)-1-propanone from spruce wood and these two derivatives together with their 4-hydroxy-3,5-dimethoxyphenyl honiologs from maple wood are the only, as yet, isolable cleavage products of each ethanol lignin fraction indicates that they are either primary cleavage products or, as now seems
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