SUBJECT: PHARMACEUTICAL ORGANIC CHEMISTRY

Transcription

S.A.RAJA PHARMACY COLLEGEVADAKKANGULAM 627 116SUBJECT: PHARMACEUTICALORGANIC CHEMISTRYII SEMESTER B.PHARMPRACTICAL LAB MANUAL

S.NoEXPERIMENTPREPARATION12345678Benzoic AcidIodoformSalicylic AcidUrea NitrateBenzamideAcetanilideBenzanilideAcetyl Salicylic AcidSTEREO CHEMISTRY MODEL91011MethaneEthyleneAcetyleneDETERMINATION of Melting and Boiling point1213Melting PointBoiling PointSALT ANALYSIS14151617181920212223Qualitative salt analysis Sample No-1Qualitative salt analysis Sample No-2Qualitative salt analysis Sample No-3Qualitative salt analysis Sample No-4Qualitative salt analysis Sample No-5Qualitative salt analysis Sample No-6Qualitative salt analysis Sample No-7Qualitative salt analysis Sample No-8Qualitative salt analysis Sample No-9Qualitative salt analysis Sample No-10PAGE NO.

Ex.No:Date:PREPARATION OF BENZOIC ACIDAim:To prepare and submit benzoic acid from benzamidePrinciple:Benzoic acid is an aromatic acid. It can be prepared by the reaction of benzamide withsodium hydroxide which on hydrolysis gives sodium benzoate and ammonia. It is then acidifiedwith conc. HCl to give benzoic acid.Chemical required:Benzamide1.5g10% NaOH10mlConc.HClq.sProcedure:Take 1.5g of benzamide and 10% NaOH 10ml in a round bottom flask which are mixedwell with constant stirring and heated in a water bath until ammonia gas ceases completely. Coolthe beaker and add 20ml of distilled water and then add Conc.HCl drop by drop till the solutionbecomes acidic. Filter the solution and wash with water to remove all impurities and finally driedand weighed.Recrystallisation:It is recrystallised by using hot water.Report:The amount of benzoic acid is obtained Chemical reaction:

Ex.No:Date:PREPARATION OF IODOFORMAim:To prepare and submit iodoform from acetonePrinciple:The principle involved in the preparation of iodoform is halogenation. When methyl ketone oraldehyde having CH3C o group, ethanol, is treated with halogen in the presence of base likesodium hydroxide, it undergoes aliphatic substitution to form a salt of haloform. In thispreparation acetone reacts with iodine in the presence of base like sodium hydroxide to giveiodoform, sodium acetate, sodium iodide.Chemical required:Acetone3ml10% iodine solution 10ml10% NaOHq.sProcedure:Take 3ml of acetone and 10ml of 10% iodine solution and add 10% NaOH drop by dropwith continuous stirring in a beaker until to get iodoform as a lemon yellow crystalline solid.Filter the solution and wash with cold water and finally dried and weighed.Recrystallisation:It is recrystallised by using a mixture of methanol and water in the ratio 1:1Report:The amount of iodoform is obtained Chemical reaction:CH3-Co-CH3 3I2 4NaOH CHI3 CH3COONa 3NaI 3H2O(Acetone) (Iodine)(Iodoform) (Sodium acetate) (Sodium iodide)

Ex.No:Date:PREPARATION OF BENZOIC ACIDAim:To prepare and submit salicylic acid from methyl salicylatePrinciple:Salicylic acid is an aromatic acid. It can be prepared when methyl salicylate is heatedwith sodium hydroxide which on hydrolysis gives sodium salicylate and methanol. This sodiumsalicylate undergoes acid hydrolysis with conc. HCl to give salicylic acid.Chemical required:Methyl salicylate2ml10% NaOH10mlConc.HClq.sProcedure:Take 2ml of methyl salicylate and10ml of 10% NaOH in a 10ml beaker or round bottomflask and mix well and heat. The mixture in a water bath until oily layer of methyl salicylate isdisappears. To the mixture add Conc.HCl drop by drop until the solution becomes acidic. Filterthe solution and wash with water to remove all impurities collect the precipitate and finally driedand weighed.Recrystallisation:It is recrystallised by using hot water.Report:The amount of salicylic acid is obtained Chemical reaction:

Ex.No:Date:PREPARATION OF UREA NITRATEAim:To prepare and submit urea nitrate from ureaPrinciple:The principle involved in the preparation of urea nitrate is nitration. Urea is nitrated withconcentrated nitric acid to get urea nitrateChemical required:Urea2gConc. HNO34mlDistilled water8mlProcedure:Take 2g of urea and dissolve in 8ml of distilled water and make into a saturated solutionin a 100ml beaker and stirred well. To this add concentrated nitric acid drop by drop until theprecipitate of urea nitrate is obtained. Wash the precipitate with concentrated nitric acid andfinally dried and weighed.Report:The amount of urea nitrate is obtained Chemical reaction:H2N-Co-NH2 HONO2 (Urea)(Conc. nitric acid)H2N-Co-NH2 .HNO3(Urea nitrate)

Ex.No:Date:PREPARATION OF BENZAMIDEAim:To prepare and submit benzamide from benzoyl chloridePrinciple:Benzamide is an aromatic amide. It can be prepared by the action of benzoyl chloridewith aqueous ammonia solution. It gives benzamide and hydrochloric acid. The formedhydrochloric acid is neutralized with excess of ammonia as ammonium chloride.Chemical required:Benzoyl chloride5mlConc. ammonia solution10mlProcedure:Take 10ml of Conc. ammonia solution in an iodine flask cool in a ice bath. To this add5ml of benzoyl chloride gradually and shake the flask frequently until the precipitate ofbenzamide is obtained. Collect the precipitate and wash with water to remove all impurities andfinally dried and weighed.Recrystallisation:It is recrystallised by using hot water.Report:The amount of benzamide is obtained Chemical reaction:

Ex.No:Date:PREPARATION OF ACETANILIDEAim:To prepare and submit acetanilide from anilinePrinciple:The principle involved in the preparation of acetanilide is acetylation. Acetylation is done byusing a mixture of acetic anhydride and sodium acetate or acetic anhydride and acetic acid.When aniline is treated with acetic anhydride and sodium acetate, it gets acetylated to giveacetanilide.Chemical required:Aniline3mlAcetic anhydride4mlSodium acetate12.5mlConc.HCl2.5mlProcedure:Take 100ml of water in a 250ml clean conical flask and add 2.5ml of Conc.HCl andshake well. Then add 3ml of aniline and stirred well until aniline completely passes into solutionas anilinium ion. Add 4ml of acetic anhydride to the resulting solution until it dissolvescompletely. Add 12.5ml of 33% sodium acetate and stirred well vigorously cool the solution. Itis then filtered and wash with water to remove impurities and finally dried and weighed.Recrystallisation:It is recrystallised by using hot waterReport:The amount of acetanilide is obtained Chemical reaction:

Ex.No:Date:PREPARATION OF BENZANILIDEAim:To prepare and submit benzanilide from anilinePrinciple:Benzanilide is an aromatic anilide. The principle involved in the preparation ofbenzanilide is benzoylation. When treated with benzoyl chloride in the presence of aqueoussodium hydroxide to give benzanilide. The aqueous sodium hydroxide is used to remove benzoylchloride which gives sodium benzoate and hydrochloric acid. This reaction is called SchottenBoumann method of benzoylation.Chemical required:Aniline3mlBenzoyl chloride5ml10% NaOH4mlAlcohol5mlProcedure:Take 3ml of aniline and 40ml of 10% of sodium hydroxide in a 250ml of conical flaskand mix well. To this add 5ml of benzoyl chloride and shake the flask continuously for 15-20minutes,until the smell of benzoyl chloride ceases completely. Collect the precipitate and washwith water and finally dried and weighed.Recrystallisation:It is re-crystallised by using alcohol.Report:The amount of benzanilide is obtained Chemical reaction:

Ex.No:Date:PREPARATION OF ACETYL SALICYLIC ACIDAim:To prepare and submit acetyl salicylic acid from salicylic acidPrinciple:Acetyl salicylic acid is an aromatic acid. It can be prepared when salicylic acid is treatedwith acetic anhydride or acetyl chloride in the presence of concentrated sulphuric acid. It getsacetylated to give acetyl salicylic acidChemical required:Salicylic acid2gAcetic anhydride4mlConc.H2SO43-4 dropsProcedure:Take 2g of salicylic acid and 4ml of acetic anhydride in a 100ml clean dry conical flask.To this add 3-4 drops of Conc.H2SO4 and shake well for 15 minutes until the precipitate ofacetyl salicylic acid is obtained. To this add 50ml of distilled water and filter the solution.Collect the precipitate and finally dried and weighed.Recrystallisation:It is recrystallised by using hot ethanol or boiling water.Report:The amount of acetyl salicylic acid is obtained Chemical reaction:

STEREO CHEMISTRY MODELEx.No:Date:METHANEAim:To make a stereo model of methane by using ball and stick molecules and explain the formationof bonds, bond angles and bond length.Description:Shape of the moleculeTetrahedralBond angle1090 28’Bond length1.09A0Bond energy102K Cal/ mole(To break any one of the bonds of methane)Hybridization:Four Sp3 orbital are found by the interaction of its one S orbital and three p orbital to givea four new equivalent orbital of identical (some energy and shape)The four Sp3 orbital are arranged in such a way that their axis are directed towards thecorners of the regular tetrahedral with carbon located at the center.Each carbon- hydrogen covalent bond in methane is formed by overlap of one Sp3 orbitalfrom carbon and one s from hydrogen.

Ex.No:Date:ETHYLENEAim:To make a stereo model of ethylene by using ball and stick models and explain the formation ofbonds, bond angles and bond length.Description:Bond angle1200Bond length(C C)1.34A0Bond Length(C-H)1.09A0Hybridization:The ethylene, carbon atoms are Sp2. The two Sp2 hybridized carbons are attached to eachother by σ bond and π bond. The σ bond results from the overlap of unhybridized p orbital. Theremaining Sp2 orbital form σ bond with either carbon (or) hydrogen atom. Ethylene is a planarmolecule and is trigonal shape. The carbon-carbon double bond in alkenes is made of one σ bondand π bond.

Ex.No:Date:ACETYLENEAim:To make a stereo model of acetylene by using ball and stick models and explain the formation ofbonds, bond angles and bond length.Description:Bond angle1800Bond length (C C)1.20A0Bond length (C-H)1.09 A0Bond energy (C-C)123-199 K Cal/ moleHybridization:In this molecule the hybridization of one s- orbital and one p- orbital to form twoequivalent collinear orbital which are directed in straight line with an angle of 180 0. The othertwo p- orbital remained pure.In acetylene one of the Sp orbital of each carbon atom overlap with one another along theaxis to form C-C σ bond. The remaining one Sp orbital of each carbon atom overlap with two sorbital of hydrogen atom to form two C-H σ bond. The left pure p-orbital (py,pz) of each carbonatom containing electrons overlap to form two π molecule orbital. This π molecule orbital at rightangle to each other and the result is a molecule in which π electron density cylindricallysymmetrical about linear Sp bond.

Ex.No:Date:DETERMINATION OF MELTING POINTAim:To determine the melting point of the given sample.Principle:The melting point is defined as the temperature of which the liquid and solid forms of acompound exist in its equilibrium with each other. The pure compounds have very short meltingrange where as impure compounds have wide melting point hence if a substance is not pure itwill not melt over 0-50C range or less while the other compounds of ordinary purity will meltover at a range of 1-20C.Procedure:A small amount of the substance is powdered well in a clean porous plate with the help ofspatula. A fine capillary tube of 8cm length is taken and sealed at one end by insulating in aBunsen blue flame. The material is filled in the tube by pressing through the open end withsample kept in a watch glass and then tapping the closed end gently on a desk in order to forcethe sample down to the bottom. The process of tapping is repeated till the packed substance inthe capillary tube stands 3-4mm from the sealed end. A 50ml glass beaker is half filled withliquid paraffin and then it is placed on wire gauze supported by tripod stand. A thermometer iskept front in a iron stand with the help of a cork it is covered into beaker, So that the bulb is wellimmersed in liquid paraffin the capillary tube which is with the substance is tied withthermometer. The tip of thermometer and capillary tube are in same level.Now the beaker is slowly heated by means of Bunsen burner and the liquid paraffin isstirred gently at the same time watch the substance in the capillary tube and mercury level in thethermometer. As the substance shows the melting at once the burns is removed and stirring ofboth is continued. The temperature will rise very slowly when some of the substance in thecapillary tube rises the temperature on the thermometer is noted.The above determinations are repeated twice after cooling the bath and take freshcapillary tube each time. The mean of the three reading gives exact melting point of substance.Note:Don’t take a large amount of liquid in a heating bath it will take a long time to heat andthus causes unnecessary delay.At high temperature the stirring of bath becomes unnecessary because the conventionalcurrent that are set up heat the bath uniformly.Sometimes sulphuric acid in the beaker become blackish, to decolourise the bath addpotassium nitrate will oxidize the crystals before warming. The nitric acid produced will oxidizethe colouring matter and the bath becomes colourless.For cooling the bath liquid paraffin or sulphuric acid stir it in or mixed it with same freshliquid of substance. Keep melting over a wide range of temperature it is impure. A puresubstance must have sharp melting point.The liquid paraffin bath should be free from water molecule otherwise the liquid mayexplode.Report:

The melting point of given sample is Melting Point of some pure compoundsS.NoCompound nameMelting Point of pure compoundin 0c123456789101112131415Benzoic acidSalicylic acidAcetanilideAspirinHydroquinone DiacetateIodoform2,4,6- Tribromo AnilidePara Bromo AnilideUrea NitratePicric Acid5-NitroSalicylic acidBenzanilide2-Naphthyl BenzoateBenzamideFormic Acid121158114135122119119167163162236162115129200

Ex.No:Date:DETERMINATION OF BOILING POINTAim:To determine the boiling point of the given sample.Principle:A pure organic compound liquid boils at a fixed temperature which is characteristic ofthat substance.Procedure:When only a small quantities of liquid its boiling point is determined by the capillarytube method. A few drops of liquid are placed in a thin walled small test tube. A capillary tubesealed at about 1cm from one end is dropped on to it. The glass tube containing the liquid andcapillary is then tied along the thermometer is then so that liquid stands near tube. Thethermometer is then dipped in a beaker containing paraffin oil or sulphuric acid.The beaker is heated and the bath liquid stirred continuously with using a stirrer when theboiling point is reached bubble starts in a rapid stream from the lower end of capillary tube .Thethermometer is read .The evolution of bubbles is just stopped and the experiment is repeated.The mean of the two reading is taken to be correct boiling point.Report:The boiling point of given sample is

S.NoCompound NameBP in correctedDegree in Celsius tophenonePhenyl SalicylateChloroformEthyl alcoholEthyl 3

GENERAL SCHEME FOR IDENTIFICATION OF ORGANIC COMPOUNDSExperimentPreliminary testPhysical idMay be acids ones,nitro compoundsColourlessAcids, c Nitro compoundsBrown or blackPhenols ,aminesPleasant Fruityalcohols,estersFishy or ammoniacalAmines ,hydrocarbonsKerosene likeHydrocarbonsPungent and irritatingAcids ,acid halidesBitter AlmondsMay be benzaldehyde ,urea,thioureaCold waterSolubleAromatic acidsHot waterSoluble5%Sodium bicarbonate solnSoluble with effervesenceCarboxylic acidPhenols , acids5%sodium hydroxide*Soluble and reappears onadding Hcl*Soluble and turns yellow orbrown when boiled*Soluble or oily layerdisappears on boiling andforms white ppt onacidification with HclSugars ,Aliphatic aldehydeEsters or amides of aromatic acidAminesDil Hcl solnSoluble

EstersCon H2So4SolubleLitmus paper testAminesDissolve the substance and dipthe litmus paperRed to BluePhenols or acidsBlue to redNeutral Ferric chloride soln testAdd one or two drops ofNeutral Ferric chloride solnPhenolsViolet,blue ,greenᾳ NaphtholsWhite pptᵦ NaphtholsGreen colourCarboxylic acidsBrown ppt or buff colourHydroxy acidsYellowAromatic /Aliphatic1.Ignition testA small quantity of substance isignited on a nickel spatulaAliphatic compoundBurns with Nonsmoky flameAromatic compound2.Nitration test(Electrophilicsubstitution)To a little of substance add amixture of 1ml of conc.HNO3and 1ml of Con H2So4.It isthen heated on a water bath forhalf an hour and poured into abeaker containing 25 ml ofwaterBurns with smoky flameAliphatic compoundColourless solnAromatic compoundYellow colour solnSaturated /Unsaturated1.Little of substance is shakenwith water and add Brominewater2.Little of substance isdissolved in Carbon tetrachloride and Bromine water isadded in dropsYellow colour decolourisedUnsaturatedYellow colour persistsSaturatedYellow colour decolourisedUnsaturated

Baeyers testYellow colour persistsSaturatedLittle of substance is shakenwith water and add one drop ofSodium carbonate solution andone or two drops of Dil Kmno4solutionPink colour decolourisedUnsaturatedPink colour persistsSaturatedTest for Elements(Nitrogen,sulphur ,halogens)Sodium fusion test(Lassaigne’s test)Add a small piece of freshly cut oil free sodium metal in a clean ignition tube . Heat it on the flameto melt it.Add little of the given sample ,heat it to red hot,and plunge immediately into about 10ml ofdistilled water in a china dish .Crush the fusion tube and boil the mixture for 5 minutes and filtered.Thissolution is called sodium fusion extract (SFE)Test for NitrogenTo 1ml of SFE in a test tubeadd few drops of freshlyprepared ferrous sulphatepowder.Heat it ,cool andacidify using Dil sulphuricacidPrussian blue or green colour isformedPresence of nitrogenViolet,red or purple colourPresence of sulphurTest for Sulphur1.To 1 ml of SFE add one ortwo drops of freshly prepared

sodium Nitroprusside soln2.To 1 ml of SFE add a dropof lead acetate solutionBlack pptPresence of sulphurConformatory test forCarbohydratesBorsche’s reagentA small quantity of 2,4 Dinitrophenyl hydrazine is moistenedwith con H2So4 and then addmethyl alcohol and the givensubstance .Heat it in waterbathYellowish orange colourPresence of aldehyde or ketoneWith Schiff’s reagentViolet colourPresence of aldehydeSub Tollensreagent(ammoniacal silvernitrate) and heat itSilver mirror at the sides oftesttubePresence of carbohydratesReddish brown pptPresence of CarbohydratesViolet ring at the junction oftwo liquidsPresence of CarbohydratesYellow pptPresence of CarbohydratesBlue to redPresence of Carboxylic acidBrisk effervescencePresence of Carboxylic acidFruity odourPresence of Carboxylic acidSub Fehlings reagentA&B,heat it in a water bathMolisch testTo the solution of thesubstance add alcoholic alphanaphthol and then addConcH2SO4 along the sides ofthe test tubeOsazone testSub water ,add phenylhydrazine.Heat for 5 minutesin waterbathConformatory test forCarboxylic acidTo the solution of thesubstance dip a glass rod andapply over Litmus paperSubstance sodiumbicarbonate solutionSubstance little ethanol and adrop of Con.H2SO4.Heat it in

water bath for 5 miutesFluorescein testSub equal quantity ofresorcinol and moistened witha drop of Con H2SO4.Heat for5 to 10 minutes and pour itinto a beaker containingSodium hydroxide solnIntense greenish yellowfluorescencePresence of Dicarboxylic acidWhite PptPresence of estersViolet of deep reddish brownPresence of estersBlue or violetPhenol,resorcinolPink or whiteAlpha naphtholGreen to whiteBeta naphtholYellowPhenolic acidBlue green or blue violet colourPhenolsConformatory test for EstersHydrolysisSub is refluxed withConcentrated solution ofsodium hydroxide and thenacidify with Con HclHydroxamic acid testSub 1 ml ofHydroxylamine hydrochloridein alcohol.To this add 1ml ofsodium hydroxide and boilgently for 2 min.Acidify withdil hcl and add two drops offerric chloride solnConformatory test forPhenolsFerric chloride testSub Alcoholic or aqueous5%ferric chloride solnLiebermann reactionSub in a dry test tube add 1 mlof Conc H2SO4 ,few sodiumNitrite crystals heat it inwaterbath ,pour into beakerhaving sodium hydroxide solnPhthalein testHeat the substance withphthalic anhydride and a drop

of Con H2SO4 for 2 minutes.Cool and pour the contents tosodium hydroxide solutionGreenFaint greenPhenolsAlpha or beta naphtholsBromine water is added to dilaqueous soln of phenolsSilky white pptPhenolsSub 1ml of dil NaoH solutionand one drop of CHCL3,warmthe mixtureBlue colourAlpha or beta naphtholsDifferentiation for alpha andbeta naphtholsWarm with pinch of substance,Carbon tetra chloride andcopper powderBlue colourAlpha naphtholsBrownish colourBeta naphtholsSub alcohol and add picricacidReddish pinkAlpha naphtholsOrange colourBeta naphtholsSoluble and gets precipitated onadding sodium hydroxideAminesConformatory test forAminesSub dil HclNitrous acid testSub Con Hcl cool it in icebath.Add a cold solution ofSodium nitriteDye testSub dil Hcl,cool and addSodium nitrite solution ,thenadd cold solution of Alkalinebetanaphthol solutionTo the substance solution addbromine waterSub glacial acetic acid and0.5 ml of acetic anhydride heatit gently and pour into water ina beakerBubbles of nitrogen gasAminesOrange red dyeAminesWhite pptAminesWhite crystalsAmines

Conformatory test forAmidesHeat the sub with sodiumhydroxide solutionAmmonia gas is evolvedAmidesHeat the sub Con. HNo3White pptAmidesSub oxalic acid solnWhite pptAmidesViolet colourDiamidesWhite pptAmidesDeep redPresence of ThioureaBiuret testA little of sub is gentlyheated in a dry testtube to meltit.add 1 ml of sodiumhydroxide soln cool and add 2drops of copper sulphatesolutionSub aniline heat it and coolConformatory test forThioureaFerric chloride testSub in a dry test tube isheated ,add dil sodiumhydroxide soln ,acidify withdil Hcl,add drop of ferricchloride solutionWarm the sub with alcoholicyellow mercuric oxide in a testtubeSub 1 ml of dil acetic acid,heat it,add 1 ml of potassiumferro cyanide solutionBlack pptPresence of thio ureaGreen colour changing to bluePresence of thio urea

SUBJECT: PHARMACEUTICAL ORGANIC CHEMISTRY II SEMESTER B.PHARM PRACTICAL LAB MANUAL . S.No EXPERIMENT PAGE NO. PREPARATION 1 Benzoic Acid 2 Iodoform 3 Salicylic Acid 4 Urea Nitrate 5 Benzamide 6 Acetanilide 7 Benzanilide 8 Acetyl Salicylic A