Examining Vanillin And Its Properties Biology Essay

Vanillin ( 4-hydroxy-3-methoxybenzaldehyde ) is an of import flavorer agent largely used in drinks, pharmaceutical industries, nutrient merchandises, etc. Naturally present as a vanillin glucoside in vanilla cods and used as an intermediate in the synthesis of some drugs. Vanillin possesses antimicrobic and antioxidant belongingss.

In the yesteryear, production of vanillin is really expensive and a really long procedure. Vanillin was obtained from the oxidization of lignin, or from ferulic acerb tract or some other tracts. The chemical production of vanillin from assorted methods had been described.

The method used in this research is High selectivity in the oxidization of Mandelic acid derived functions and in O-Methylation of Protocatechualdehyde. The get downing stuff used here was catechol and nowadays this method is used for the industrial production of vanillin. The method used was boring but produces vanillin in good output.

The analysis of obtained vanillin was done by utilizing Thin Layer Chromatography and Infrared Spectroscopy. Infrared spectrum of obtained merchandise and mention spectrum of vanillin were compared. The similarity of runing points of the obtained merchandise and vanillin from literatures shows that the merchandise obtained can be confirmed as vanillin.


Vanillin ( 4-hydroxy-3-methoxybanzaldehyde ) is a chief portion of natural vanilla. It is a major flavorer agent used widely in the nutrient and dairy merchandises, drinks and pharmaceutical industries etc. It is an organic aromatic compound which contains three functional groups ( aldehyde, phenol and quintessence ) . Vanillin is obtained from the beans or cods of Vanilla works ( Vanilla planifolia ) . Its beginning is from the semitropical woods of Mexico and Central America. Mayan and Aztec civilisations are the first who discover the belongingss of vanilla. It was foremost extracted by Nicholas Theodore Gobley in 1858.1

Vanilla Planifolia Vanilla cods Vanilla beans

In newly harvested vanilla cods vanillin is binds with the ?-D-glycoside.

Today vanillin is used in the readying of many pharmaceutical readyings like Papaverine, Levodopa, Levomethyldopa and antimicrobic agent Trimethoprim and besides for the production of weedkillers and antifoaming agents. Vanillin besides has belongingss like antioxidants and anti-tumor. Due to its aromatic belongingss it is widely used in the air fresheners, aromas, incense and candle.1

Vanillin is extracted from the vanilla beans but due to its low natural production and high demand it is prepared by assorted man-made methods like chemical synthesis, enzymatic synthesis etc.1



Percentage dry weight

Vanilla plantifolia



Vanilla tahitiensis



Hyacinth ( Hyacinthus orientalis )

Roots, basal home base

0.2- 0.5

Narcissus ( Triandrus narcissi )

Roots, basal home base


Solanum tuberosum ( Potato )

Tuber tegument


Proboscidae cuisianica

Roots, Pod


Vanilla pompona


0.01 or less

Siam benjamin

Vascular tissue exudations


Natural happening of vanillin in different plants3

Vanillin Production








Entire Vanillin Production4

Physiochemical belongingss of Vanillin:

Vanillin is a white crystalline pulverization which has a thaw point about 820C. The pureness is by and large above 99.0 % w/w on dried footing. Vanillin has a characteristic pleasant odor and gustatory sensation for which it is widely used in the universe. The boiling point of vanillin is about 1540C and its sublimation temperature is reported to be 700C. Vanillin starts to break up at 1600C. Vanillin has a vapour force per unit area of 0.0022 hPa at 250C and 0.0017 hPa at 650C and saturated air has a concentration of 0.00029 % at 250C, matching to 18.0 mg/m3. The vapour denseness of vanillin is found to be 5.3 at 250C. Its evident specific gravitation is 0.6 kg/dm3. Specific gravitation of vanillin is reported to be 1056 kg/m3 at 200C. Vanillin is soluble in H2O and its solubility additions with increasing temperature. Its solubility in H2O at 25 & A ; deg ; C was reported to be 10g/L. Vanillin was reported to be readily soluble in intoxicant ( ethyl alcohol ) . Besides vanillin shows little solubility in ethyl propanone, methyl alcohol, and diethyl ether. The Octanol/ Water divider coefficient was found to be 1.21 which indicates that vanillin is improbable to bio accumulate. The pH of vanillin in H2O is 4.3. The phenol group of vanillin has a pKa value of 7.38. With increasing pH the molecule will lose a proton, go negatively charged and more soluble in H2O. Vanillin dissolves in dilute solution of base hydroxides.16

Production of vanillin:

The production of vanillin is a really long and expensive procedure which involves big figure of stairss every bit good. The pollenation of flowers has to be done manually as there is deficiency of natural pollinators. The flowers have to be pollinated within 24 hours to bear fruits. The vanilla beans require 10- 12 months to maturate from the clip of pollenation. The full-blown vanilla beans are xanthous green, and are acrimonious in gustatory sensation. The full-blown beans lack the characteristic vanilla spirit which merely develops upon hardening, which involves three stairss.

1 ) Killing, the green beans are treated with assortment of methods such as scalded with hot H2O, exposed to sun, wilted in the oven, scarred, treated with ethene gas, or stop dead to interrupt tissue unity. The 2nd method is the cheapest but most labour- intensive. In this measure tissues wholly lose their unity, but still contains high sum of wet which has to be removed by the perspiration procedure. This measure runs for 7-10 yearss, during wet content of the beans reduced to 60- 70 % . After losing the wet the beans turn dark brown in coloring material and start to develop their characteristic vanilla spirit. To cut down microbic spoilage and to concentrate the spirit, the wet content were farther reduced to 25- 30 % . After this measure, the beans are stored in closed containers to make their highest spirit content and so their conditioning is done either by hot H2O intervention or by sun drying.5

2 ) Procedure of bring arounding and drying together requires 4-5 months. The healed beans cods may be covered with bantam crystals of vanillin. This coating is known as givre, which sometimes used as standard for quality assessment.6

3 ) During the agitation procedure, vanillin is released from its non-volatile glucoside by the action of vanilla ?-glucosidase on vanillin glucoside.3 Vanillin entirely is non present in the infusion of V. Plantifolia, some related phenylpropanoid ( C3-C6 ) compounds [ chiefly p-hydroxybenzaldehyde ( 8.6 % ) , vanillic acid ( 4.3 % ) , p-hydroxybenzyl methyl quintessence ( 0.9 % ) ] are besides present which gives the alone spirit to natural vanilla.7,8,9

However, vanillin has besides been found to be present in hints sum in workss like baccy, fruits and fruit merchandises like orange, Citrus paradisi, and tangerine. In Mangifera indica, vanillin is present both as ‘free vanillin ‘ and ‘vanillyl glucoside ‘ . It is besides reported to be present in elderberry juice, blueberries, orange juice, strawberries, passion fruit juice, bloodsuckers, and vinos. It has besides been found in diverse nutrient merchandises such as Zea mays everta, extruded oat flour, apple cyder brandy, commercial liquid fume flavorers, mushrooms and chocolate.3, 10

Vanillin is added in the concentrations runing from 1 to 26 milimolar in the nutrient merchandises which depend upon the nature of the merchandise. Vanillin has a low spirit threshold value of 20µg/L in H2O at 20 & A ; deg ; C.11Although more than 12000 metric tons of vanillin are produced each twelvemonth merely 1 % of it comes from the natural beginnings and the remainder are synthesized by chemical synthesis.12 Furthermore, the high demand for vanillin and the fact that the vanillin derived from workss is comparatively expensive ( $ 1200- 1400 per kg compared to synthetically bring forth which is & A ; lt ; $ 15 per kg ) , because of causes such as scare handiness of vanilla cods, clime associated fluctuations of the harvest outputs, labor-intensive cultivation, pollenation, reaping and hardening of pods.13

These grounds has led to the geographic expedition of other biotechnological paths such as the microbic production from phenolic stilbenes, lignin, eugenol, and ferulic acid.8, 11 Vanillin can be obtained from chemical synthesis, biotransformation or from debasement of waste sulphite liquors.11

What is Vanilla infusion?

It is full of the flavorful and odorous rules of the full-blown cods, and is one of the largely used flavorer olfactory property. The olfactory property of vanilla cods developed during the agitation procedure after picking. Because of the cleavage of glycosidic bonds, vanillin aromatic acids, aldehyde and intoxicants are liberated. Kernels are prepared by the direct extraction of the cods with aqueous ethyl alcohols or by thining the concentrated infusion.

The high cost and demand of vanilla extract lead to debasement and blending. Infusions are adulterated by add-on of spirits like natural vanillin obtained from lignin, or more tasting ethyl vanillin. Sometimes coumarin besides added. It is hence indispensable to command the quality of the vanillin extracts to declare them as reliable. Several methods are used for the hallmark of vanillin infusions such as AOAC methods which apply GC, TLC and PC methods. But some of this methods are clip devouring and arduous. As natural vanillin contains more heavy hydrogen and carbon-13 as compared to man-made vanillin, one manner could be the finding of stable isotope ratio of vanillin by mass spectrometry. One alternate method for this is the finding of stable isotope ratio of other compounds ( 4- hydroxybenzaldehyde, 4-hydroxybenzoicacid ) or the measuring of the site-specific natural isotope ratio of deuterium/hydrogen by atomic magnetic resonance ( SNIF-NMR ) .

Because vanilla infusion are really complex in their composing, the analysis of constituents happening in reliable vanilla infusion at certain concentrations, is another manner to qualify vanilla infusion. Assorted chromatographic methods are used for the separation of vanilla infusions such as Gas Chromatography, Gas Liquid Chromatography and High Performance Liquid Chromatography.14

General method for isolation of vanillin from infusion:

Vanilla infusion incorporating about 0.1 g of vanillin were diluted with H2O or methanol/water ( 1:1 v/v ) depending on their intoxicant and sugar content, severally. This is so extracted three times with 25 milliliters of diethyl quintessence. The combined organic infusions were concentrated on a revolving evaporator to a syrupy liquid. The residue was taken up in ethyl alcohol and diluted with H2O to an intoxicant content of less than 30 % . Concluding volume was measured to be 7 milliliter. The solution was cleared by filtrating through a paper filter.15

Chemical methods of synthesis of vanillin

In 1876 Reimer-Tiemann method for the extraction of vanillin was used from guaiacol with an alkalic solution of chloroform.1

In early twentieth century chemists found another beginning of vanillin and that was lignin and after 1920s most of vanillin was obtained from lignin waste.

The authoritative method for the production of vanillin is by isomerization of eugenol into isoeuginol and oxidization of isoeuginol to vanillin.1

Vanillin ‘s molecular expression is C8H8O3 and molecular weight is 152.1 g/mol holding functional groups like ether, aldehyde and phenol. Vanillin is white to somewhat yellowish in coloring material in the signifier of crystalline pulverization or acerate leafs, which is somewhat soluble in H2O, freely soluble in intoxicant. It has a runing point of 81-84oC2 and boiling point at 285oC and its denseness is 1.056 g/cm3.2

But today vanillin is synthesized by reaction of guaiacol with glyoxylic acid to obtain catechol and than vanillin. This is how we are bring forthing a batch of vanillin today.1

In research labs vanillin is produced from 4-hydroxybenzaldehyde.1

Biosynthetic method of natural vanillin production:

Several biosynthetic paths have been proposed for the biogenesis of natural vanillin. In 1965, the first biosynthetic path was proposed by Zenk. He proposed a biosynthetic tract in which vanillin was derived from ferulic acid. In this path Zenk described that foremost ?- oxidization of ferulic acid leads to formation of vanilloyl-CoA which was so reduced to vanillin or instead can be deacylated to vanillic acid.

The formation of vanillin from ferulic acid by Zenk.

The 2nd biosynthetic path was proposed by Funk and Brodelius in 1990 and 1992 based on the consequences of feeding wireless labelled compounds to vanilla tissue civilizations. They proposed a really complex procedure in which caffeic acid was foremost methylated at 4- place to iso-ferulic acid which was so farther methylated at 3-position to bring forth 3,4- dimethoxycinnamic acid. It was so demethylated at the 4- place. After which glucosylation leads to the production of vanillic acid this was so reduced to organize vanillin.3, 5

The formation of vanillic acid from isoferulic acid

Kanisawa et Al. in 1994 proposed a really complex path which came from measurings of the degrees of simple phenolic compounds and their glucosides during the clip class of development of vanilla pods.5

Vanillin production by Kanisawa et Al.

A really interesting mechanism was derived for formation of vanillin by Overhage et Al. in 1999. In this path he described the formation of ferulic acid from eugenol and the formation of vanillin from ferulic acid.3, 5

Vanillin Production by Overhage et Al.

Biotechnological methods of the production of vanillin

Enzymatic methods:

Vanillin can be obtained from vanilla cods by utilizing readyings incorporating ?-glucosidase which helps to let go of vanillin from cods. This method can be used as an option to conventional hardening. Enzymes can besides be used to bring forth vanillin from other works stuff by biotransformation. For illustration: Soybean lipoxygenase produces vanillin from esters of coniferyl intoxicant. Van den Heuvel et Al. used Penicillium flavoenzyme to bring forth vanillin by biotransformation of vanillylamine and of cresol.7

Cell or tissue civilization:

This technique has been used for old ages to bring forth vanillin. The benefit of this technique is that with the production of vanillin some of the different compounds can be prepared which are present in the vanilla cods. For illustration: vanilla cells and variety meats and cells of Capsicum frutescens have been successfully cultured and found to roll up vanillin and other metabolites. But the disadvantage is that the production of vanillin is ever low with these techniques. Some steps had been taken to increase the output of vanillin by these paths. Like eating of putative precursors, the usage of endocrines or elicitors, usage of adsorbent such as wood coal, and accommodation of environmental civilization conditions. But none of these steps had been able to bring forth vanillin in good yield.7

Familial technology for vanillin in workss:

By usage of familial technology a new manner of vanillin production from workss had been proposed by Brodelius and Xue. They proposed to present an enzyme or tract to bring forth vanillin from a mainstream intermediate of the works phenylpropanoid tract. By isolation of HCHL ( 4-hydroxycinnamoyl-CoA hydratase/lyase ) enzyme, had raised some possibilities for vanillin production. For illustration: feruloyl-CoA, which is an intermediate in works monolignol tract, could be converted to vanillin and acetyl-CoA in a individual measure. Any vanillin obtained via familial alteration would non be in a free province but would be converted to its ?-D-glucoside. However, one time the vanillin is formed it will be really hard to forestall it from oxidization and decrease. It requires the down ordinance of the enzyme activities responsible which would had to be identified and their cistrons isolated. It may be possible that the enzymes will execute some other critical maps which will interfere with vanillin production.7

Pharmacokineticss of Vanillin:

Vanillin can be given orally, or by hypodermic, intraperitoneal, and endovenous path. Metamorphosis of vanillin outputs chiefly vanillic acid and glucuronide and sulphate conjugates which are excreted in urine along with other metabolites. 94 % per centum of an unwritten dosage of 100 mg/kg vanillin was excreted as urinary metabolites and unchanged vanillin within 48 hours of intervention.

Absorption: No information for soaking up of vanillin is found in worlds. The acute toxicity of vanillin in animate beings exposed orally and by intraperitoneal, hypodermic, and endovenous injections indicates that it is absorbed by those paths. Systemic effects observed in animate beings following unwritten sub chronic intervention with vanillin further indicates that GI soaking up occurs.

Distribution: No information was found sing the distribution of vanillin.

Metamorphosis: Metamorphosis of vanillin in worlds outputs vanillic acid. 100mg/kg of vanillin given to rats outputs chiefly glucuronide and sulfate conjugates in piss within 24 hours of intervention after 48 hours, 94 % of vanillin dosage was accounted for: 7 % as vanillin, 19 % as vanillyl intoxicant, 47 % as vanillic acid, 19 % as vanilloylglycine, 8 % as catechol, 2 % as 4-methylcatechol, 0.5 % as guaiacol, and 0.6 % as 4-methylguaiacol. Vanillin administered intraperitoneally to rats gave rise to several urinary metabolites, dwelling chiefly of vanillic acid in both free and conjugated signifiers, and smaller sums of conjugated vanillin, conjugated vanillyl intoxicant, and catechol.

Elimination: Vanillin given to rats either orally or intraperitoneally excretes vanillin or its metabolites in piss. 94 % of an unwritten dosage of 100 mg/kg was excreted as urinary metabolites and unchanged vanillin within 48 hours of treatment.17

Uses of Vanillin

Vanillin is used as seasoning agent in the nutrient industry, normally in cocoa and ice- pick industry. 75 % of vanillin produced is used in these two cocoa and ice-cream industries and remainder of 25 % is used in confectioneries and baking industry.18 Besides vanillin has been found to continue nutrient as it is an antioxidant and antibacterial belongingss. Researches besides shows that cowss who eat vanilla flavored nutrient addition more weight because they eat more.18

Vanillin as an intermediate merchandise in the synthesis of assorted drugs like Levodopa, L-Methyldopa, and Trimethoprim etc.18




Levodopa is chiefly used in the intervention of Parkinson ‘s disease, a easy progressive disease which alters the cells of significant nigger. These cells produce a chemical called Dopastat. Dopamine is given to the patient in the signifier of Levodopa because Dopastat is non able to traverse blood encephalon barrier.18

L-Methyldopa is used in the intervention of the high blood pressure and has a vasodilative effect.18

Trimethoprim is an antibiotic comes under the category of chemotherapeutic agents and it is chiefly used in the intervention of the urinary piece of land infections.18

Anticarcinogenic belongingss

Karran and Durant carried out surveies that prove that vanillin has Anticarcinogenic effects. These surveies proves that vanillin belongs to the DNA-PK inhibitor family.19

Anticlastonegic belongingss

Surveies carried out by Keshava et Al shows that vanillin has an ability to cut down chromosomal harm caused by X raies and UV light.20

Antimicrobial Properties

Another survey carried out by Fitzgerald et al proves the strong Antimicrobial belongingss of the vanillin. It was discovered that during agitation vanillin is bioconverted into vanillyl intoxicant and vanillic acid but it was found that neither of these metabolites were antagonist to yeast growth.21

Antitumor Properties

Antitumor belongings of vanillin is proved by a survey carried out by Lirdprapamongko et Al on a mouse theoretical account shows that vanillin is a fresh inhibitor of category 1 P13K enzymes, presence of an aldehyde group in the vanillin construction is of import for the suppression. Vanillin besides shows suppression of HGF-induced malignant neoplastic disease cell migration and to cut down angiogenesis in-vivo.22, 23

Vanillin Prodrug ( MX-1520 )

A paper by Zhang et al published in The British Journal of Hematology shows that a vanillin prodrug had successfully been made which reduces red blood cell sickling in rats with reaping hook cell mutant. Vanillin bonds to the reaping hook haemoglobin and inhibits cells sickling in-vitro but in instance of in-vivo vanillin is degraded in the digestive piece of land before being functional in the organic structure. To forestall this debasement MX-1520 was prepared as a prodrug of vanillin which shows 30 times more bioavailability so vanillin.24


Vanillin can be synthesized by assorted methods. In this undertaking vanillin was synthesized by High selectivity in the oxidization of Mandelic acid derived functions and in O-Methylation of Protocatechualdehyde.25

Chemicals used: catechol, aluminum oxide, glyoxylic acid, Na hydrated oxide solutions, ethyl ethanoate, Cu chloride dihydrate, dichloro methane, diethyl quintessence, trichloromethane, methyl alcohol, hydrochloric acid and Na sulfate.

Instruments and Glassware: Beakers, Conical flasks, pipettes, mensurating cylinder, Watch glass, Separating funnels, Magnetic scaremonger, Oil bath, and Thermometer.

Chemical reaction for the synthesis of Vanillin:25

Monomethylation of catechol ( Preparation of 3, 4-dihydroxy mandelic acid ) .

5.00 g of catechol was dissolved in aqueous NaOH ( 3.21g in 55.0 milliliter of H2O ) in a beaker and to it 2.04 g of Aluminium oxide was added. Then after 5 min. 7.10g glyoxylic acid was added and the reaction mixture was heated at 600C for 24 hours under vigorous stirring. Then the reaction was allowed to precipitate for 10 min. After precipitation was complete, the reaction was filtered to take Al2O3. The obtained filter bar was washed with 20ml of NaOH solution. The basic lavation H2O was combined with the H2O solution and this was acidified to pH 3- 4 with 6.0 milliliters of 37 % HCl and extracted with ethyl ethanoate to retrieve the unreacted catechol. The aqueous solution was farther acidified to pH 1-2 by 2 milliliters of concentrated HCl and extracted with ethyl ethanoate to obtained mandelic acid derivatives.25

Electrophilic Substitution of glyoxylic acid on guaiacol ( Preparation of Protocatechualdehyde ) .

2g of 3, 4-dihydroxymandelic acid was dissolved in 140ml of ethyl ethanoate and individually 11.11g of Cucl2.2H2O was dissolved in 30 milliliter of H2O. These two solutions were assorted by vigorous stirring and heated for 5 hours under N ambiance at 600C. After the 5 hr continuance clip the two stages separated in organic and aqueous stage. The solution was transferred to a separating funnel and the organic stage was removed. The analysis of merchandise confirmed the transition of mandelic acid derived functions to protocatechualdehyde. The output of the merchandise was calculated and analysis was done by taking TLC and IR.25

Catalytic Oxidative, Decarboxylation of VMA ( Preparation of vanillin ) .

7.2 milliliter of protocatechualdehyde and 0.8 milliliter of NaOH were assorted and dissolved in 25 milliliter of H2O ; 20 milliliter of dichloro methane was added to the above solution. To this solution 0.5 milliliter of diethyl quintessence was added dropwise under vigorous stirring during 1 hr at a temperature of 55-60oC. The reaction was run farther for 4 hr at the same temperature. This solution was transferred to a separating funnel and two stages were separated. The aqueous stage was extracted with 2×25 milliliters of CH2Cl2. Then the organic beds were combined and dried with Na sulfate. After that the dissolver was removed under vacuity and the coveted merchandise was obtained. The output of the merchandise was calculated and analysis was done by TLC and IR.25


Synthesis of 3, 4- dihydroxymandelic acid:

Weight of empty boat-1.04g

Weight of boat + NaOH-4.25g

Weight of NaOH-3.21g

Weight of empty boat-1.03g

Weight of boat + catechol-6.03g

Weight of catechol taken-5.00g

Molecular weight of catechol C6H6O2-110.1g

Molecular weight of 3, 4- dihydroxymandelic acid C8H8O5 – 184.15g.

Weight of catechol taken – 5.00g

Weight of merchandise obtained-6.12g

Theoretical output = =

= 8.36 g

Practical output =


= 73.20 %

So, the per centum practical output was found to be 73.20 %

Properties of merchandise obtained:

State- solid

Colour- white

Odour- feature

Melting point- 130-1320C

Analysis of merchandise:

TLC- Solvent for TLC was prepared by blending 75ml of ethyl ethanoate and 25 milliliter of trichloromethane. The consequence obtained as follows:

Rf of get downing stuff

Rf =

= 5.6/6.9

= 0.81

Rf of 3, 4- dihydroxymandelic acid = 7.1/ 7.5

= 0.94

Infrared spectrum of get downing material catechol:


Wavenumbers ( cm-1 )

Assigned structural characteristics


-OH stretch, H-bonded of phenol


-CH-CH stretch


-C=C of catechol karyon


-C-C of catechol karyon


Aromatic -C=C stretch


-C=O of catechol karyon

Reference IR Spectrum of Catechol

hypertext transfer protocol: //riodb01.ibase.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cg

Infrared spectrum of 3, 4- dihydroxymandelic acid:

3,4-dihydroxymandelic acid

Wavenumbers ( cm-1 )

Assigned structural characteristics


-OH stretch, H-bonded of phenol


Aromatic -C=C- stretch


O-H stretch of carboxylic acid


-C=O stretch of carboxylic acid


Ortho disubstituted

Reference IR Spectra of 3, 4-dihydroxymandelic acid

hypertext transfer protocol: //riodb01.ibase.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi

From the infrared spectrum of both the above compounds it can be seen that a carboxylic group gets attached to the catechol.

Synthesis of protocatechualdehyde:

Weight of empty boat- 1.05g

Weight of reactant + boat- 3.05g

Weight of reactant taken-2g

Weight of merchandise obtained-1.14g

Theoretical output =


= 1.5 g

Practical output =


= 76.00 %

So, the per centum practical output was found to be 76.00 %

Properties of merchandise obtained:

State- liquid

Colour- greenish

Odour- feature

Melting point- 148-1490C

Analysis of merchandise:

TLC- Solvent for TLC was prepared by blending 75ml of ethyl ethanoate and 25 milliliter of trichloromethane. The consequence obtained as follows:

Rf value of merchandise

Rf =

= 6.9/7.8

= 0.88

Infrared spectrum of protocatechualdehyde:


Wavenumbers ( cm-1 )

Assigned structural characteristics


-OH stretch of phenol ( free )


-O-H stretch, H-bonded of phenol


Aromatic -C-H stretch


-C=O stretch of aromatic aldehyde


Aromatic -C=C stretch

Reference IR spectrum of protocatechualdehyde

hypertext transfer protocol: //riodb01.ibase.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi

Synthesis of vanillin:

Weight of empty vial – 10.04g

Weight of vial + reactant-17.24g

Weight of reactant taken-7.2g

Weight of merchandise obtained-5.25g

Molecular weight of protocatechualdehyde C7H6O3-138.12g

Molecular weight of vanillin C8H8O3-152.15g

Weight of reactant taken-7.2g

Weight of merchandise obtained- 5.25g

Theoretical output =


= 7.93 g

Practical output =


= 66.20 %

So, the per centum practical output was found to be 66.20 %

Properties of merchandise obtained:

State- solid

Colour- white

Odour- Sweet

Melting point- 83-850C

Analysis of merchandise obtained:

TLC- Solvent for TLC was prepared by fade outing 75ml of ethyl ethanoate, 15ml of acetic acid and 10 milliliter of trichloromethane.

Rf value of merchandise

Rf =

= 2.3/ 8.1

= 0.28

Infrared spectrum of vanillin:


Wavenumbers ( cm-1 )

Assigned structural characteristics


-OH stretch of phenol ( free )


Aromatic -C-H stretch


-C=O aromatic aldehyde


Aromatic -C=C- stretch


Aromatic -C=O quintessence stretch

Reference IR Spectrum of Vanillin

hypertext transfer protocol: //riodb01.ibase.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi


The consequences obtained from the IR spectrum of catechol were matched with the criterions. It means that the catechol used was pure and of a good quality. The IR spectrums of catechol and 3, 4- dihydroxymandelic acid were matched and it can be seen that considerable alterations has been occurred. A carboxylic group was attached at the disbursal of a H ion. The IR spectrum of catechol shows a weak wide set due to the intermolecular H bonded -OH in the part of 3004- 3500 cm-1. The fingerprint part of catechol was weak set at 1261.7 cm-1 which gets matched with the criterions ( Sang-Hee Jang et Al, 2002 ) . While the fingerprint part for the measure 1 merchandise i.e. 3, 4- dihydroxymandelic acid was found at 1715.6 cm-1 which shows a -C=O stretch of carboxylic acid.

The consequences of analysis of protocatechualdehyde about match with the criterions. The Rf value of protocatechualdehyde was calculated to be 0.88 which about lucifers with the criterion of 0.90. The fingerprint part for protocatechualdehyde was found to be at 1710.2 cm-1 which matches with the criterion for -C=O stretch for aromatic aldehyde as shown by the IR correlativity tabular arraies. This can corroborate that the merchandise obtained was protocatechualdehyde.

The criterion Rf value of vanillin from literature is 0.35+/- 0.3. The calculate value of vanillin was found to be 0.28. The deliberate value for vanillin about lucifers with that of criterion. The output of vanillin obtained is 66.20 % . The runing point of obtained merchandise is 83-85 0C, which matches with the standard thaw point ( 81-840C ) of vanillin in literatures. The infrared spectrum of vanillin shows a -C=O stretch for aromatic aldehyde and an aromatic -C-O stretch for an quintessence which are alone fingerprint parts for vanillin. These figures shows that the merchandise obtained can be regarded as vanillin.

Decision: The consequences obtained from the thin bed chromatography and spectrums obtained from the Infrared spectroscopy about lucifers with the standard values from the literatures. Besides the runing points of the obtained merchandise and of vanillin cited from the literatures are similar. This can corroborate that the obtained merchandise was vanillin. The output of vanillin obtained was rather good.

Future work: In hereafter there is a demand to develop a method which should non be excessively long and should be simple for the synthesis of vanillin.