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Aldehydes and ketons. Formaldehyde. Acetaldehyde. Chloral hydrate. Benzaldehyde . Aceton . Acetophenone . It contains variety of chemical compound including benzoate, ceosol ,, benzaldehyde , y- terpineol , nerolidol , isohytol , phytol and acetic acid.
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Aldehydes and ketons • Formaldehyde. • Acetaldehyde. • Chloral hydrate. • Benzaldehyde. • Aceton. • Acetophenone.
It contains variety of chemical compound including benzoate, ceosol,, benzaldehyde, y-terpineol, nerolidol, isohytol, phytol and acetic acid Chloral Hydrate is a sedative/hypnotic drug used to treat insomnia
Acid base character All neutral
Preliminary test Soda lime test: Only for solid Few chlorahydrate +few soda lime in mortor →sweety odor of chloroform odor Do not smell
30%NaOH : • It is done for compound with no ᾳ hydrogen like aromatic aldehyde( bezaldehyde) and formaldehyde: • In this case Called self oxidation –reduction reaction . • Called cannizzaro᾿s reaction. • Difficult to be done ( need time and high temp.) Methanol + formic acid Benzyl alc.+ benzoic acid
in case of compound with ᾳ hydrogen like acteldehyde. • Called aldol condensation: • Dil acetaldehyde + xss 30% NaOH →yellow resin of bad apple odor B-hydroxy aldehyde
Chlorahydrate: chlor. +30%NaOH on cold but some times need to warm → sweety odor of chloroform +oily droplet. Aceton and acetophenone: no reaction. • Fecl3: • All no reaction. • Conc. H2SO4: • no reaction with all except with chlorahydrate. • Few chlorahydrate + Conc. H2SO4 on cold →sepration of oily layer of chloral
General test • 2,4 dinitrophenyl hydrazine test: • silver mirror test (tollen᾿s reagent test or ammonical silver nitrate test: • fehling reagent test or fehling reduction test
2,4 dinitrophenyl hydrazine test Formaldehyde acetaldehyde Chlorahydrateaceton Benzaldehyde acetophenone
formaldehyde: yellow ppt. Acetaldehyde: yellow orange ppt. Chlorahydrate: no reaction ( yellow color) Aceton: orange yellow ppt. Benzaldehyde: orange ppt. Acetophenone: orange ppt.
silver mirror test (tollen᾿s reagent test or (ammonical silver nitrate test tollen᾿s reagent: 1-5 ml of silver nbitrate + 1 dp 10% NaOH →black ppt. of Ag2O (SLIVER OXIDE) + dil. NH4OH until clear solution obtained 1 ml tollen᾿s reagent + 1ml aldehydes or ketons heat on water bath for 10 minutes then cool on rack
Formaldehyde and acetaldehyde: rapidly give silver mirror. Chlorahydrate and benzaldehyde: silver mirror after longer time on the water bath. Aceton and acetophenone : no reaction..
fehling reagent test or fehling reduction test Mix equal amount of fehling A + B to give blue color of cupric ion Few aldehydes or ketons + few Na2CO3 + fehling mix and put it in water bath Formaldehyde actaldehyde : rapidly change in color. Chlorahydrat and benzaldehyde: take longer time to change the color. yellow or red ppt. of cuprous oxide Aceton and acetophenone: no reaction
chlorahydrate • Soda lime test: sweety odor of chloroform. • Conc. H2SO4: sepration of chloral layer. • 30% NaOH: oily droplet and chloroform odor
IRlocation • C-H stretching band of aliphatic under 3000 cm -1. • C-H stretching band of aromatic above 3000 cm-1. • Carbonyl group stretching band of aldehyde at 1725 cm-1. • Carbonyl group stretching band of ketone at 1715 cm-1