Vanillin Derivatives

Safrole, which is both toxic and carcinogenic, occurs in sassafras oil up to 90%. There are two commercially important sassafras oils the Brazilian oil is obtained from the trunk wood of Ocotea pretiosa and the Chinese oil is obtained from Cinnamomum camphora by steam distillation of wood chips. Safrole from 

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Vanilla flavour is not only determined and characterised by the vanillin molecule, but also by many more phenolic compounds and vanillin derivatives. Two examples of molecules that recently obtained FEMA-GRAS status are vanillyl ethyl ether and vanillin 2,3-butanediol acetal (Scheme 13.11). Vanillin can be hydrogenated to form vanillyl alcohol, which is also used in vanilla flavours. Vanillyl alcohol can be reacted with ethanol to form vanillyl ethyl ether. Vanillin can also form an acetal with 2,3-butanediol (obtained by fermentation of sugars) catalysed byp-toluene sulfonic acid in toluene. 

Fig. 14.2 shows a partial retrosynthetic analysis for the three routes A, B,and C discussd and reveals many unexplored possibilities for the synthesis of morphine. Continued attempts have teen made to find new routes to its ring sytem. Thus a photocyclisation of an aryloxyenone (Fig. 14.2, scheme type D) (ref. 187), a methodology based upon the use of a metallated enamine (ref. 188), and a route employing a vanillin derivative and its reaction with a 2-allylcyclohex-2-ol have been described, the last two of which gave racemic morphine (ref. 189). 

The first so-called aromatic compounds to be studied seriously, such as vanillin (derived from vanilla), had two obvious properties. They had a sweet smell and were remarkably stable. This last property was the reef on which many of the early theories of chemical bonding foundered. Consider benzene. Kekule knew that its molecular formula was C H. The only way he could rationalise this formula with the known properties of benzene, was to imagine the six carbon atoms joined in a ring and connected by three alternate double bonds. This is where the trouble started because double bonds are supposed to confer reactivity on an organic molecule benzene is stable. Double bonds can readily be added to for example, they will undergo fast reactions with bromine and sulphuric acid to give simple "addition" compounds. The reagents simply "add" across the double bond. 

Because vanillin is a phenol aldehyde, it is stable to autooxidation and does not undergo the Cannizzarro reaction. Numerous derivatives can be prepared by etherification or esterification of the hydroxy group and by aldol condensation at the aldehyde group. AH three functional groups in vanillin are... 

In detergent perfumes, the stabiUty of vanillin is not always certain. It depends on the association made with other raw materials, eg, with patchouli, frankincense, cloves, most of the animal notes, and such chemicals as amyl saUcylate, methyl ionones, heflotropin, gamma undecalactone, linalool, methyl anthrarulate, benzyl acetate, phenyl ethyl alcohol, cedar wood derivatives, oak mosses, coumarin, benzoin. Pern balsam, and cistus derivatives. In some cases, these mixtures can cause discoloration effects. 

L-Dopa and Trimethoprim are two other dmgs that can be made from vanillin. u-Dopa is used for the treatment of Parkinson s disease Trimethoprim is an antiinfective agent used mainly for urinary tract infections and certain venereal diseases. Also, Mebeverine, an antispasmodic agent, and Verazide, a generic antitubercular agent, are dmgs that can be made from vanillin or its derivatives. 

In the 1990s hplc has become widely used in the flavor and fragrance industry to measure vanillin and other phenoHc compounds. Routine methods have been developed that are particularly adapted to thermosensitive products, such as vanillin and its derivative products, with elution gradient and uv detection at given wavelengths. Certain critical impurities can thus routinely be traced to very low (10 ppm) concentrations. 

Purified by recrystn from aqueous MeOH. It is estimated colorimetrically with H3PO4 in EtOH followed by vanillin and HCl [Hayward and Seymour i4/w/ Chem 20 572 1948]. The 3,5-dinitrobenzoyl derivative has m 92-93°. [J Am Chem Soc 83 3114 7967.]... 

Classical examples of this type of reaction are the various dimethylaminobenz-aldehyde reagents (q.v.) and vanillin-acid reagents, of which one, the vanillin-phosphoric acid reagent, is already included in Volume 1 a. The aldol condensation of estrogens is an example for the reaction mechanism (cf. Chapter 2, Table 6). According to Maiowan indole derivatives react in a similar manner [1]. Longo has postulated that catechins yield intensely colored triphenylmethane dyes [2]. 

Aromatic aldehydes react in basic as well acidic medium. Thus vanillin and primary amines yield Schiff s bases (cf. vanillin-potassium hydroxide reagent in Volume 1 a). Colored phenolates are formed at the same time. As would be expected secondary amines, indole derivatives and lysergic acid derivatives do not react. 

Note The reagent can also be applied by first treating the chromatogram with an unacidified solution of vanillin and then exposing it to hydrochloric acid vapor [3, 9], Catechin derivatives should be evaluated rapidly (within 10 min), since the red coloration is not stable in daylight and fades relatively quickly [5, 9]. 

Catechol is also obtained from coal coking and from certain wood residues. Vanillin (synthetic vanilla flavoring) is a catechol derivative. Resorcinol and hydroquinone are currently made by the same type of chemistry used... 

The use of the lignin fraction is much more cumbersome currently the best-known chemical of a real commercial importance is vanillin, which is obtained by oxidation of the black liquor. Another example is a product called spray-dried lignosulfonate (as sodium salt) obtained from the older, acidic sulfite pulping process. It is sold as a commercial product primarily as a concrete additive for enhanced strength. Since the cement industry is one of the big contributors of carbon dioxide emissions (due to the production of calcium oxide from calcium carbonate), the use of this renewable, wood-derived product not only is fossil-carbon neutral in itself but also reduces carbon dioxide emission due to the diminished need for cement in large infrastructures made of concrete. 

To correlate these changes in absorption with theory, the ultraviolet spectroscopic behavior of model compounds closely related to the degradation products isolated from bagasse native lignin, i.e., p-hydr-oxybenzaldehyde, vanillin and syringaldehyde, was determined. The compounds used were p-hydroxypropiophenone, vanillin, acetovanillone and acetosyringone and their derivatives. 

Pearl, I. A., and D. Beyer Reactions of Vanillin and Derived Compounds. 

Certain derivatives of the lignin sulfonic acids can be determined directly in water. The nitroso derivatives, which are easily formed in solution, can be determined by differential pulse polarography [438]. Vanillin can be formed by alkaline hydrolysis [439] or alkaline nitrobenzene oxidation [440], extracted into an organic solvent and determined by gas chromatography. 

These are materials that are synthetic but are the same compound as is present in a natural flavouring material. From time to time it emerges that one substance produces a given flavour. Most chemists know that benzaldehyde has a smell of almonds. Some chemists know that hydrogen cyanide smells of bitter almonds. If a natural flavouring can be represented by a single substance and that substance can be synthesised then the flavour is likely to be available as a nature identical flavour. Vanilla flavour is a good example. Vanilla flavour can be all natural and derived from vanilla pods or nature identical or artificial. The nature identical product would be based on vanillin, which is in vanilla pods and has a flavour of vanilla. An artificial vanilla flavour would be ethyl vanillin, which is not present in vanilla pods but has a flavour two and a... 

Riedel A process for making vanillin from guiacol derived from catechol. Invented by J. D. Riedel in 1932. 

Essential oils are organic compounds derived from flowers, seeds, leaves, roots, resins, and citrus fruits. The structures of many fragrant compounds have been studied, and processes for making these valuable compounds in a laboratory have been developed. There are now approximately 5000 synthetically produced chemicals that are available to a perfumer. These chemicals include vanillin, rose oxides, and the damascenes, or rose ketones. 

Tyramine is derived by using 4-hydroxybenzaldehyde as the starting material. Vanillin and 0-vanillin can also be used in this synthesis to make the tyramine analogs 2-hydroxy-3-methoxy-B-phenylethylamine and 3-methoxy-4-hydroxy-B-phenylethylamine, respectively. Vanillin is less suspicious to purchase and the potency and elfects of the vanillin made drug are about the same as Tyramine. 

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