Aldehydes and Ketones

double bond between a carbon and an oxygen

two alkyl groups bonded to a carbonyl carbon

one alkyl group and one hydrogen bonded to a carbonyl carbon

-e of alkane name is replaced by -al methane -> methanal ethane -> ethanal

Formaldehyde (methanal) Acetalaldehyde (ethanal) Propionaldehyde (propanal) Butyraldehyde (butanal) Valeraldehyde (pentanal)

-carbaldehyde cyclopentanecarbaldehyde

-e of alkane is replaced with -one ketones as substituents are using oxo or keto prefixes 2-propanone 2 butanone 3-oxobutanoic acid

dipole of carbonyl is stronger than the dipole of alcohol due to double bond of oxygen being more electron withdrawing this increases intermolecular attractions and increasing boiling point but less than alcohols due to lack of H bonding act as electrophiles due to the negative charge on the oxygen aldehydes are more reactive towards nucleophiles due to less sterics and fewer alkyl donating groups

Primary Alcohol with PCC (parital oxidation) too much oxidation leads to carboxylic acid!

Secondary Alchol with Sodium/Potassium Dichromate salts or CrO3 or PCC stops at ketone stage

adding of Nu to a carbonyl compound carbonyl carbon is the electrophile 1) Nu forms covalent bond with carbonyl carbon breaking the pi bond 2) pi bond electrons go to the oxygen and its negative with extra electons 3) O- now accepts a proton (H) to form an alcohol IF a leaving group is present, the carbonyl can reform as the leaving group leaves instead

in presense of water, aldehydes and ketones form geminal diols 1) waters oxygen attacks carbonyl carbon 2) O- takes the H from the bonded water resulting in two alcohol groups or a diol proceeds slowly but rate increases with acid/base addition

like hydration but when one equivalent of alcohol is used 1) ROH oxygen attacks carbonyl carbon 2) O- takes H from alchol leading to OH and OR group

like hemiacetal formation but two equivalents of alcohol are used (Sn1) 1) ROH oxygen attacks carbonyl carbon 2) O- takes H from alcohol and forms OH and OR group 3) OH gets protonated in acidic conditions and leaves as second equivalent attacks the formed carbocation acetal made with aldehyde ketal made with ketone

compound with nitrogen atom double bonded to a carbon attom condensation reaction 1) NH3 attacks carbonyl carbon forming O- 2) O- gets protonated twiceand leaves as a water, 3) NH3 loses a hydrogen and uses lone pair to form double bond with carbonyl carbon with NH2 4) NH2 loses a hydrogen to form water and a stable NH R-C- R C= NH

nucleophiles electrophilic

tautomerized imines where a couble bond and a nitrogen group exist

hydrogen cyanide is a nucleophile with tripple bonds AND an electronegative nitrogen atom making it acidic 1) Hydrogen dissociates, making the cyanide anion nucleophilic and attack the carbonyl carbon 2) O- picks up an H forming an OH occurs when HCN reacts with aldehyde/ketones stability gained from new C-C bond

when further oxidized, they form carboxylic acids potassium permanganate chromium trioxide silveroxide hydrogen peroxide

aldehydes and ketones can be reduced to alcohols with hydride reagents LiALH4 and NaBH4