ALDEHYDES, KETONES

reactions of carbonyl groups

oxidation, reduction, addition, substitution

aldehydes undergo oxidation to form

carboxylic acids, acid derivates

aldehyde reagent for conversion to carboxylic acids

chromic acid, permanganate

what's used to test presence of aldehydes

ammoniacal silver nitrate as oxidizing agent to form carboxylic acid (via oxidation) and reduced silver metal

substituent group of alcohol

hydroxy

how many carbons must be present in simplest ketone

3

jones test (test for, positive result, negative result)

• primary, secondary alcohols

• turns orange

• remains blue/green

tollens test (test for, positive result, negative result)

• aldehydes

• silver mirror

• not clear, clear solution

iodoform (test for, positive result, negative result)

• methyl ketones/ethanol

• yellow precipitate

• no yellow precipitate

2,4 dnph (test for, positive result, negative result)

• aldehydes, ketones

• orange/red precipitate

• no precipitate, clear solution

formaldehyde results (jones, tollens, iodoform, dnph)

+ + - +

aliphatic aldehyde (oxidized to carboxylic acid)

benzaldehyde results (jones, tollens, iodoform, dnph)** double check result in post lab discussion may 2.

- + - +

aromatic aldehyde BUT it reacts slower

acetone (jones, tollens, iodoform, dnph)

- - + +

methyl ketone (resistant to mild oxidation)

aldehydes oxidize to

carboxylic acids

carboxylic acids reduce to __

primary alcohols

(they do not oxidize tho)