PRACTICAL ORGANIC CHEMISTRY PURIFICATION METHODS LASSAIGNE'S METHOD DISTILLATION TECHNIQUES (detection of elements) en Element] Sedium Confirmed test (A) SIMPLE DISTILLATION |g) rRacTionAL ‘extract Conditions ewe Tine sane fas von | DISTILLATION) | [luogen] Ne FN InecreS0 NOH) volatfe impurles iflerence Is sFechecone: HCI -»FedFetCNi (i) When bling point derence |p, ferences 10K wien fFeCoreone HCI FeuFelen is 30 K or more. ca ide ean {i Crude of in (i) Mixture of chloroform petroleum (BP = 334K) and Aniline industry o ean (8 Reston (529 9 oe i) Mire of Eber tnd Meth caphar thao a5 NadFeOWy nn sak athe aex) |__| Sulphur | 20 ENadFelcNNo Tottene (yp. = 384) 1 (i) Hane 948K) and ws Tole 384K) (©) DISTILLATION UNDER REDUCED PRESSURE Wacssum distitetion) When guid bolls at higher temperature and it may decompose before bp. is tained Tioga buanx | Nak HINO, = Agno Example i) Concentration of sugar juice eM White ppt. soluble in a9 i) Glycerol NaX {i} Yellow ppt. partially soluble inag NA cons @) STEAM DISTILLATION 5 ta Yalow ppt. insole i When the sbstance P=? + P, Nicos " mnie with water and | Vapour Vapour Vapour a ad peountieeme seem (i) Aniline is separated sa itrogenl Naicenss | Asi leslfornitogen;insead ol itm veer, and mp | aeeasin ad (ii) Turpentine oil (iil) Nitro Benzene sulphur IN ane Shot ms presence i) Brome Berwene (0) Naphthalene together oiNane {a o-Nitophenel, QUANTITATIVE ANALYSIS OF ORGANIC COMPOUNDS (Estimation of carbon and hydrogen) ESTIMATION OF NITROGEN The “Leebigs method Dumais method: The nitrogen containing organic CH,+ 0, —+xC0, + ¥2H0]} Co pmund ied nsopen ges om featng kth copper fl) oxen 12, woh 0, 2 -100|| the presence of CO, sas ot © 44 vt of org. compd 00 2 2 wl H,O. of HA, AHO # 18 wt. of org compd 100 mixture of gases is collected over potassium hydroxide solution in Which CO, is absorbed and volume of mitogen gas is determined [Note : This method is suitable for (Ltt) tstinaton i ergnic compound conaing we Cand tony In ee trather element || % of Nex BNP | op fg, N.S, halogens av alsa preset the 08 | We organic compound wil slo give thei oo ‘oxides which i being absorbed in KOH| and wil inewase the percentage ofcarbon| and therefore following modification should be made Note compounds This method can be sstimatennogen inal pes of organic ‘Kjeldaht's method: In this method nitrogen containing] /compound is heated with cone, H,SO, in presence of copper sulphate to convert nitrogen into ammonium sulphate which is| decomposed with excess of alkalito liberate ammonia. The ammonia evolved is 114 volume of acid (ml) normality of acid ‘wi of organic compound Note: Tis mathod is simpler nd more convenient snd i ainiy used for fining out the parcennge of izogen i food stuffs, sol, ferilers and varous| tact produc This mchod cannot ne wed | compound having nie groups azo group EN = No} and nisogen nthe tng (pte, quince ee} Since zogen In these compounds & ol quantlively % of N ferried tno rerum alate ——_——DISTINCTION BETWEEN PAIRS OF COMPOUNDS UNSATURATION TEST {a} Double’iiple bonded Compounds (C = Cy(C=C)+ Br, in CC), (Brown colour) > Coloutless compound Br Br + R-CH=CH-R+ Br SSeR-CH-CH-R (Ateneo feaowsed Br Br R-C=C-R+ Br, Se R-G-¢-R . TAlbsne) (Broun Br (colouies) (b) Double/Tiiple bonded Compounds + Baeyer's reagent (Pink colour) —» Brown precipitate + R-CH= CH- Ri KMnO.—» R- CH- CH - Rt MnO, Chuan | teat Sa ou beeen + R-C=C-R' +KMnO, > MnO, +RCOOH-R'COOH ‘pot, dite) “Brown sb + R-C=C-H+KMnO, MnO, + RCOOH+CO,+H,0 ‘Allyne) (Ho, cise) Broun pbt- (Coles) Baeyer's reagent is cold, dilute KMnO, solution having pink colour Note : The above test are not given by Benzene. Although it has unsaturation, TEST FOR TERMINAL ALKYNE Terminal alkyne ‘Ara White ppt Red ppt. NH,NO, +H,0+R-CaC~Ag At. NiO! Wnts NH(CL+H,0+R-CaC-Cu « 2221+ HOH] Teaon NATURE OF X-GROUP IN C-X BOND R-X + aqueous KOH—+R-OH+KX-ESt> gx FX is Cl, precipitate wil be white and for Br yellow precipitate will be obtained. DISTINCTION BETWEEN 1°,2° AND 3° ALCOHOLS i t + R-¢-on EEE R-C-al R Tern oho Coudines appears ‘mediate t i + R-CH-OH et R-CH-Cl Secondary seal Clowdines appears wethin ve inter + R-CH,- OH HHS RCH, Primary sleohst Cloutines appeses ‘fer 30 Lucas reagent is anhydrous ZnCl, + cone. HCL 9H + H,C-CH=R type of alcohols give iodoform test. on + HC-CH-R +1, allie CH, + RCOONa wile PHENOL Phenol + frre chloride —» Volt colouration oO-0tts Fao, —vairtraocany = ane Violet colouration CARBONYL GROUP ‘+ Carbonyl compound + 2,4-Dinitrophenyihydrazine > Yellowiorange crystal (Bradys reagent) NO, ON > fo-F pit -no enn) no, * NaHO, We cotton ny ge Sco + matso—+ R= 50:8 nt i gt So o.0 + NallS0, — R-&-SO.Na *Stetyl ketone cH, —-ALDEHYDE GROUP + Aldehyde + Tollen's reagent ——-> Silver minor R-CH430H" 42|AgINH,J—eRCOO® +2H,0+4NH42AG Aldehyde + Fehling’s solution > Reddish brown precpate R-C-+H42Cu"* +50H+ RCOO"+3H,0+Cu,0 Reddish brows pot) H,C-C-Rsl, NaOH “#249 CHI, + RCOONa Iedotorm (Nelow ppt) AROMATIC ALDEHYDE GROUP + Aromatic aldehyde + Tollen's reagent — Silver mirror + Aromatic aldehyde + Fehling’s solution —» Negative test Negative teteZmnin (7) ctio] oes Opv0 es itor ‘CARBOXYLIC GROUP Carbonic acid + Sodium bicarbonate effervescence RCOOH + NaHCO,—>RCOONa + H,0 + CO,* FORMIC ACID HCOOH — HCOOH) spot Primaty amine + KOH + CHC|—*"+ Isonitrle (Offensive smelt Amines (1°, 2° & 3°) (Hinsberg’s test) ‘+ Primary amine + Benzenesulphonyl chloride > Precipitate "0" 5 soluble + Secondary amine + Benzenesulphony| chlorid —> Precipitate 101 insoluble + Tertiary amine + Benzenesulphonyl chloride > No reaction ‘Note : Berzenesulphonyl chloride s called Hinsberg'sreagent Chloroethane and chlorobenzene H,-Cleaq, KOH 2246C,H,—OH+ KCI Ag + C6 09 Kori ceo reaction Chlorocyelohexane and chlorobenzene + C61 29 KOH) oF KOBE, Agel + (Pei 24, KOH ce No reaction Chloroethane and bromoethane + Cif C14 a9. KOFEM GH OF KCBS» Age! anced Tit | CBr + aq, KOHES Gt OFt+KBr SE AaB Benzyl chloride and chlorobenzene aooe—2e_ CChorebenvene Ethyl chloride and vinvl chloride + GH,-Cltag KOH 4+C,H,-OHFKCL (Bl cane age TN + H,C-CH-Clraq KOH EI sacs No reaction Vay ehoride n-Propyl alcohol and iso-propyl alcohol + CH,CH,CH,OH +HCl—#2->CH,CH,CH,C. [No cloudiness at room temp. on ¢ ch- cH, H,C-CH- CH, HEC CCloudiness within 5 minutes ————.Ethyl alcohol and methyl alcohol (Io: + CH,CH.OH + 4l, + 6NaOH—> CHI, Yalow pot + CH,OH + 41, + 6NaOH —> No yellow ppt. Ethyl alcohol and acetone (2, 4 - DNP) ° Hg 2, 4Dintrophenyhyérazine form test) HCOONa (tlw orange stl) + Hon 24-008 No teaction Phenol and ethyl alcohol (Neutral FeCl, + Phenol + Neutral ferric chloride —> Violet colouration 6) Hol + Fea, rat + eos" + 3HCL Violet coloustion + CH,CH,OH + Neutral feric chloride —-» No violet colouration Benzoic acid and phenol (NaHCO, + Benzoicacid + Sodium bicarbonate» effervescence CH,COOH + NaH#CO,+C,,000Na + C0,-+ 0. Phenol + Sodium bicarbonate —» No effervescence Phe ess acide than benole acid) Propanone and propanol (2, 4 - DNP) NH Yellow orange ery + Propanol + 2,4 Dintrophensthydrazine —>No crystals Ethanal and propanal (lodoform test) + HC C-11 +1, + NaOH CHIL, + HHCOONa Ethel ledolem Iislem poe) + HC-ck, i H band ne (Tollen's and Fehit nt ‘+ Propanal + Tollen's reagent ——> Silver mirror H,C-CH,-CH+30H +2/Ag(NH),) CH,CH,COO +2H,0+4NH,+2Ag (Giver ire + Propanal +Fehlings solution -» Reddish brown precipitate 9 i H,C-CH,-CH + 200s 50H CH,CH.COO™ + 31,0 + O,0e—4 Fete 5 Negative test + Propanone—} ea Negative test Pentan-2-one and pentan-3-one (lodoform test i + HC- CH, CH, - C~ CH, + [, + NaOH Se (Penn Zone CH, + CH,CH,CH,COONa «1 = 011, ch, CH, + + NNOH HRN yellow ppt Propanal and benzaldehyde (Fehling solution) ‘+ Propanal+ Fehlingssolution —> Reddlsh brown precipitate H,C-CH,-C-H142Cu"+50H— CH.CH,COO™43H,0+04,0 + Benzaldehyde + Fehling’s solution —» No precipitate Pr oit0 + 2c0"4 50% —e No enton Methanole acid and ethanolic acid (Tollen's & Fehling solution) Fac 4 COE + CuO + HCOOH Methanoi acd [iter imtet 5 2Agl+ CO? +H,O No brown ppt. + Ethanoic acid —} Leese No silver mirror —~-Ethanal and methanal (lodoform test) + CH.CHO+,+NoOH H4*¥4 CHI,s HCOONa Ethan Iedotorm (elow ppt) + HCHO+L+NaOH #2*+ No yellow ppt Methanal Acetophenone and benzophenone (lodoform tes tts) coorse—J 9 Benzophenone] B + CH,COOH+NaHCO, +C,H,COONa+CO,*+H,0 effervescence + Btyibenaoate + Sodium bicarbonate —rNoffrvescence Benzaldehude and acetophenone ‘+ Benzaldehyde + Tollen's reagent -» Silver mirror follen's test) CHO+30H +2(Ag(NH) ‘Toten’ reagent) p= 600 v2 0+4aNtt-2Aabe + Acetophenone + Tollen’ reagent —> Nosilver mirror Me Tt CHECI,+ 3KOH—+ CH.NC + 3KC1 + 3H,0 foe} Metis socynie (Ollersve smal 1H, + H,C-NH+CHCI,+3KOH (ale) No offensive smell Dimelhy amine Aniline and ethyl amine (Diazotisation)

Giuconic acid + 2HBr (Brown colt (Colours) + Fructose + Br, + HO ——-> Brown colour (Brown calou (ro change in colour Glucose and sucrose + Glucose + Tollen's reagent ——-> Silver mirror + Sucrose + Tollen’s reagent ——+ No silver mirror Glucose and starch + Glucose + Febling’s solution ——> Red ppt. + Starch + Fehiing's solution ——> No red ppt oR + Glucose + I,solution ——-> No blue colour + Starch + I, solution ——> Blue colour ———.