A-Methylvanillyl alcohol

This research was undertaken to study aqueous alkaline reactions of monomeric structures, similar to polymeric wood constituents, from which color would be formed. Since hardwood pulps were of the greatest immediate interest, the reaction of syringyl alcohol, representing the hardwood lignin structure, in aqueous alkaline solution at room temperature has been studied extensively up to the present time, but the reactions of vanillyl alcohol and a-methylvanillyl alcohol, representing the softwood lignin structure, have also been studied to some extent under the same reaction conditions. 

Preparation of Compounds. Methyl Ether of ck-Methyl-vanillyl Alcohol. This compound was prepared using a modified procedure for preparing vanillyl ethyl ether as described by Adler and Herne-stam 2). A 4% solution of dry hydrogen chloride in absolute methanol (210 ml.) was added dropwise in V/2 hours to a solution of a-methylvanillyl alcohol (9.5 grams) in methanol (200 ml.). During the addition, the solution was cooled at 0°C. and stirred continuously. After the mixture... 

Preparation of Reaction Solutions. In general, the reaction solutions of the aromatic alcohols (syringyl alcohol, vanillyl alcohol, and a-methylvanillyl alcohol and their ethers were prepared by adding aromatic alcohol or ether (usually 2.5 X 10-4 mole) to the solvent (water or ethanol) in a 10-ml. volumetric flask. After the model compound was dissolved, the calculated amount of a sodium hydroxide solution was added to make the reaction solution 1 1 molar (model compound to alkali). The solution was then made up to the 10 ml. mark by adding solvent. These solutions were allowed to react at room temperature for given periods. 

Color Characteristics of the Reaction Mixtures. Initial experiments in air involving the reactions of syringyl alcohol, vanillyl alcohol, and a-methylvanillyl alcohol with alkali showed both visually and spectro-photometrically that the reaction mixture of syringyl alcohol, the hardwood lignin model, and alkali was more intensely colored than either of the reaction mixtures of the guaiacyl compounds and alkali. 

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