Saligenin derivative

The chemical shifts of the carbons in the saligenin-derived portion of these compounds are not much different from those in saligenin itself, except for the methylene carbon of the methylol group (C-7 ). The chemical shift of this carbon is shifted down field as expected on formation of an ether linkage. 

Numerous methods for the synthesis of salicyl alcohol exist. These involve the reduction of salicylaldehyde or of salicylic acid and its derivatives. The alcohol can be prepared in almost theoretical yield by the reduction of salicylaldehyde with sodium amalgam, sodium borohydride, or lithium aluminum hydride by catalytic hydrogenation over platinum black or Raney nickel or by hydrogenation over platinum and ferrous chloride in alcohol. The electrolytic reduction of salicylaldehyde in sodium bicarbonate solution at a mercury cathode with carbon dioxide passed into the mixture also yields saligenin. It is formed by the electrolytic reduction at lead electrodes of salicylic acids in aqueous alcoholic solution or sodium salicylate in the presence of boric acid and sodium sulfate. Salicylamide in aqueous alcohol solution acidified with acetic acid is reduced to salicyl alcohol by sodium amalgam in 63% yield. Salicyl alcohol forms along with -hydroxybenzyl alcohol by the action of formaldehyde on phenol in the presence of sodium hydroxide or calcium oxide. High yields of salicyl alcohol from phenol and formaldehyde in the presence of a molar equivalent of ether additives have been reported (60). Phenyl metaborate prepared from phenol and boric acid yields salicyl alcohol after treatment with formaldehyde and hydrolysis (61). 

Salicin.—It derives its name from the glucoside salicin which is present in the bark of willow trees, the generic name of which is Salix, When the glucoside is hydrolyzed it yields glucose and a compound known as saligenin, which is salicylic alcohol or ortho-hydroxy benzyl alcohol, and which on oxidation yields salicylic acid. This is one of the natural sources of the acid. 

Saligenin (76) is photochemically reactive (254 nm) when irradiated in basic media (MeOH/HeO). The reaction affords phenol/formaldehyde type resins in reasonable yield. The route to the condensation process involves the formation of the enone (77) by photochemically induced expulsion of hydroxide from the phenolic anion generated from (76). This enone then reacts with another anion ultimately to build up oligomers. Evidence for this process comes from the minor products formed during the reaction. These are the ether (78) which is produced by the addition of methanol (the solvent) to the enone (77). Furthermore the diphenylmethane derivatives (79) and (80) are also formed by the condensation of two substrate molecules either with or without the addition of solvent. Products of this type are considered as good evidence for the condensation reaction proposed. ... 

So, how does willow baik compare to acetyl salicylic acid The baric contains 1-2 % of salicyl derivatives, most of them as glycosides. The main ingredient is salicin (Fig. 3.42), which is also responsible for the bitter taste. In the intestine, sali-cin is solely hydrolyzed to give saligenin (salicyl alcohol), which turns into salicylic acid in the blood stream. The actual anti-inflammatoiy effect belongs to salicylic acid. 

Simple phenols are scarce and, in general, they are found as heterosides in plants. Phenolic acids are grouped into benzoic acid derivatives and cinnamic acid derivatives. The most relevant extracted phenols used in cosmetics are arbutin, vanillin and salicylic alcohol or saligenin. 

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