Guaiacol carbonate

Because of its bitter taste and water iasolubiUty, guaiacol has been chemically modified to improve its properties. Sulfonation provides a mixture of guaiacol-4- and 5-sulfonic acids which, as the potassium salts, is water-soluble, comparatively tasteless, but less active than guaiacol. Treatment of the sodium salt of guaiacol with phosgene provides guaiacol carbonate [553-17-1] (3) which also lacks the bitter taste of guaiacol, but is less water-soluble. 

Nencki introduced salol in 1886 and. so pre.sented to the science of therapy the "salol principle." In salol. two toxic sub.stances (phenol and salicylic acid) were combined into an e.ster that taken internally slowly hydroly/es in the intestine to give the antiseptic action of its components. This type of ester is referred to as a full. salol or true salol when toth components of the ester are active compounds. Examples are guaiacol benzoate. /3-naphthol benzoate, and salol. The salol principle can be applied to esters in which only the alcohol or the acid is the toxic, active or corrosive portion this type is called a partial salol. Examples of partial sulols that contain an active acid arc ethyl salicylate and methyl salicylate. Examples of partial sulols that contain an active phenol are creosote carbonate, thymol carbonate, and guaiacol carbonate. Althtxigh many. salol-typc compounds have been prepared and used tu. some extent, none is presently... 

Odorless needles from ethanol, rap 88.1 Faint taste of guaiacol. Practically inso] in water. At room temp 1 g dissolves in 60m] ethanol, 1 ml chloroform, IS ml ether. Much more sol in hot alcohol, hot benzene, hot chloroform. Slight ]y so] in liq fatty adds. At 20 , 100 g of glycerol (d 1.2612) will dissolve 0.043 g of guaiacol carbonate. Difficult to hydrolyze. Upon ingestion much is excreted unchanged. 

However, some last minute experimentation aimed at improving the hydrolytic stability of the polyethylene terephthalate backbone lead to bisphenol-A polycarbonate. The simple molecule, guaiacol carbonate, provided the key to this transition since it was known to be very resistant to hydrolysis. This lead to the concept of preparing bis-guaiacol polycarbonate as the basis for a more hydrolytically stable wire enamel. There was no bis-guaiacol in the stockroom so bisphenol-A was selected as a model. 

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