Org Chem

Enriquez Erika Laiza D.

Pharm-1B

EXPERIENT NUMBER

TEST PERFORMED

EXPECTED POSITIVE RESULT

7

Solubility in Miscibility/ concentrate homogenous d H2SO4 mixture

7

Ignition test

Yellow flame and soot

7

Baeyer’s test

Decolorization of a purple solution and formation of a brown precipitate

PRINCIPLE REACTION

OF

It will be miscible only if it does not form a heterogenous mixture. In which, miscibility determines solubility of liquid compounds. To determine the aromaticity of a compund. Aromatic compounds burn with sooty flame due to the incomplete combustion which causes the formation of an unburned carbon. In terms of degree of luminosity, aromatic compound > unsaturatedhydroc arbon > saturated hydrocarbon. Baeyer’s test is a test for unsaturation or double bonds. Baeyer’s test uses a solution called the Baeyer’s reagent, which is a solution of alkaline potassium permanganate.

EXAMPLES OF COUMPOUNDS THAT GIVE POSITIVE RESULTS

Cyclohexene

Hexane, cyclohexane, benzene, toluene

cyclohexene

7

Bromine test Decolorization of an orange solution

7

Test for Produce a aromaticity: yellow Nitration globule or a yellow oily layer

7

Basic oxidation

8

Beilstein Green (on a Test: Copper nonHalide Test luminous flame)

8

Sn1 Reactivity: Reaction with Alcoholic AgNO3

Violet solution or a brown precipitate

White precipitate

Bromine test which is also a test for double bonds. The reagent used is 0.5% Br2 in CCl4. To determine for the Aromaticity of a compound, Nitration test was accomplished.The samples were reacted with HNO3 and H2SO4. A test for alkylated aromatics or arenes. The reagents used were 2% KMnO4 and 10%NaOH. The loop was cooled and dipped into the solid or liquid sample. And the loop was heated together with the sample in the inner zone to the outer zone of a non luminous flame. A bluegreen (or green) colored flame was observed to indicate the presence of chlorine, bromine or iodine. The kinetics of the reactionis dependent on the alkyl halide. The more stablethe carbocation intermediate the faster the rate of SN1 reaction. A

Toluene, hexane, heptane, cyclohexene, toluene toluene

toluene

N-butyl chloride, secbutyl chloride, tert-butyl chloride, chlorobenzene

N-butyl chloride, secbutyl chloride, tert-butyl chloride

8

9

good leaving group was important for the reaction to occur. The SN1 reaction happens when substrate dissociate to a carbocation in a slowrate-limiting step, followed by a rapid attack of a nucleophile. Sn2 White The kinetics of this Reactivity: precipitate reaction was Reaction dependent on the with NaI in alkyl halide and Acteone nucleophile. Due to steric effect, the substrate effect in SN1 reaction was the opposite in SN2 reactions. It favors primary and secondary substrates. A strong nucleophile was needed for reaction to occur because it parallels basicity. TheSN2 reaction favors primary and secondary substrates compared to SN2 reaction that favors tertiary substrates. Solubility of no Cloudiness of the alcohol in cloudiness solution indicated water resulted after insolubility of that the addition specific alcohol to of 2.0 mL water. The amount water of water needed to

N-butyl chloride, secbutyl chloride, tert-butyl chloride

Ethanol, nbutyl alcohol, sec-butyl alcohol, tertbutyl alcohol

9

Lucas test

rate of formation of cloudy suspension or the formation of two layers

9

Chromic Blue-green Acid Test solution (Jones Oxidation)

produce homogenous dispersion was also observed. The reaction mechanism involved in the Lucas test is based on SN1 reaction, which depends on the formation of stable carbocations. Reactivity of alcohols in SN1 reaction is3˚ > 2˚> 1˚. 3˚ alcohols formed the second layer in less than a minute. 2˚ alcohols required 5-10 minutes while 1˚alcohols were usually unreactive. The presence of ZnCl2, a good Lewis acid, made there action mixture even more acidic; thus, it enhanced the formation of carbocations. Chromic Acid test / Jones Oxidation involved reductionoxidation or redox reaction. 1˚ and 2˚alcohols and aldehydes underwent oxidation and chromium underwent reduction from Cr6+ to Cr3+. 1˚ and 2˚

sec-butyl alcohol, tertbutyl alcohol

n-butyl alcohol, sec-butyl alcohol, nbutylraldehyde, benzaldehyde

alcohols and aldehydes reduced the orange-red chromic acid/sulphuric acid reagent to an opaque green or blue suspension of Cr (III) salts in 2-5 seconds. 1˚ alcohols reacted with chromic acid to yield aldehydes, which are further oxidized to carboxylic acids. 2˚ alcohols reacted with chromic acid to yield ketones, which do not oxidize further. 3˚ alcohols were usually unreactive and aldehydes were oxidizedto carboxylic acids. 9

2,4Dinitropheny lhydra-zone (2,4DNP/2,4DNPH) test

yellow or orange-red The reaction of precipitate 2,4-DNPH with forms aldehydes and ketones in an acidic solution is a dependable and sensitive test.Its reaction mechanism involved condensation or nucleophilic addition of NH2 to C=O andelimination of H2O. Some high molecular weight

Acetaldehyde, nbutyraldehyde, benzaldehyde, acetone, acetophenone

9

9

ketones may fail to react or may yield oils. Most aromatic aldehydes and ketones produce red dinitrophenylhydra zone while many non aromatic aldehydes and ketones produced yellow products. Fehling’s Brick-red Fehling’s test test precipitate involved reductionoxidation or redox reaction. Aldehydes were oxidized to carboxylic acids while ketones did not undergo oxidation. In here, copper was reduced from Cu2+ to Cu1+ Tollen’s Silver mirror The Tollens’ Silver Silver mirror like solution Mirror test test involved reductionoxidation or redox reaction. Aldehydes were oxidized to carboxylic acidswhile ketones did not undergo oxidation except alphahydroxyketone. Silver was reduced from Ag1+ to Ag0.

Acetaldehyde, nbutyraldehyde, benzaldehyde

acetaldehyde

9

10

Iodoform test

yellow An alkaline crystals or solution of sodium precipitate hypoiodite, formed from sodium hydroxide and iodine, converted acetaldehyde and aliphatic methyl ketones into iodoform (haloform reaction). Since the reagentwas also an oxidizing agent, alcohols which are readily oxidized to acetaldehydes or methyl ketones also gave a positive reaction. The mechanism of iodoform synthesis occurred through a series of enolate anions, which are iodinated; hydroxide displaced the Cl3anion through an addition/eliminatio n pathway. Hydrolysis Amides- blue of Acid in litmus Acid chlorides Derivatives paper acetyl chloride sample, react very Estersrapidly with water plastic to form carboxylic balloon-like acids and HCl odor (warming effectdue to the Acyl halides presence of HCl). and acid Silver nitrate also anhydridesreacted to the turbid acetyl chloride solution with producing silver warming chloride (AgCl)

Acetaldehyde, acetone, acetophenone, isopropyl alcohol

Acetyl chloride, Acetyl anhydride, Ehtyl acetate and benzamide

effect

10

Alcoholysis: SchottenBaumann Reaction

Plasticballoon odor

which was the white precipitate. The hydrolysis of esters, ethylacetate was used, occurs very slowlyand only becomes rapid with theintroduction of an aqueous acid or base. Ethyl acetate when reacted with sodium hydroxide produced the sodium salt of the carboxylic acid and an alcohol thus aplastic balloon-like odor was observed. Benzamide when reacted with 10% NaOH, produced asodium salt and ammonia, turning the red litmus paper into blue, an indication of presence of a basic substance. Acetic acid when Acetyl chloride, like reacted with acetic acid ethanol produced ethyl acetate, an ester, which was accounted for the strong plastic balloon-like odor, and water. Acetyl chloride also produced ethyl acetate, an ester with a plastic

10

Aminolysis

Oily layer

10

Hydroxamic Test

Deep burgundy color

balloon-like odor, and HCl. Acid chlorides react readily with ammonia and with 1º and 2º amines to form amides. Acetyl chloride readily formed an amide in the form of Nphenylacetanamid e or commonly known as acetanilide, as the white precipitate, and HCl, which accounts for the oily layer. Acetic anhydride reacted with aniline also produced acetanilide, the white precipitate and acetic acid, the oily layer. A preliminary test was conducted before proceeding to the main test. It was done to prevent the formation of phenols and enols that might give colors to the solution, thus giving the test an erroneous result. In test proper, hydroxylamine is treated with esters, in this experiment ethyl acetate was used, which substitute a

Acetyl chloride, acetic anhydride

Ethyl acetate

hydroxylamino (NH-OH) group for the ester alkoxyl radical. The resulting product is known as hydroxamic acid, observed as the deep burgundy color of the solution when added with FeCl3.