PORG Q2 (FINALS): Aldehydes and ketones

Aldehydes

Have at least 1 hydrogen atom attached to the carbonyl carbon

Ketones

Have two carbon groups attached to the carbonyl carbon

Carbonyl group

Acyl group

Formyl group

C=O

R-C=O

C=O -H

Acyl group in an ALD/KET

- Bonded to an atom H or C

- CAN'T stabilize a negative charge

- CAN'T act as a leaving group in a nucleophilic substitution rxn.

Acyl group in COOH

- its derivatives is bonded to an atom (O, Halogen, S, N)

- CAN stabilize a negative charge

- CAN act as a leaving group in a nucleophilic substitution rxn.

Formaldehyde (Methanal)

Common Names of Some Simple Aldehydes:

HCHO

Acetaldehyde (Ethanal)

Common Names of Some Simple Aldehydes:

Ch3CHO

acrolein (propenal)

Common Names of Some Simple Aldehydes:

H2C=CHCHO

Crotonaldehyde (2-Butenal)

Common Names of Some Simple Aldehydes:

CH3CH=CHCHO

Benzaldehyde (Benzenecarbaldehyde)

Common Names of Some Simple Aldehydes:

⌬-CHO

carbaldehyde

Cycloalkane suffix

benzenecarbaldehyde

Benzene ring suffix

Propanone (Acetone)

Simplest ketone

C-C=O-C

Boiling point

Intermediate between alcohols and alkanes

polar

The physical properties of aldehydes and ketones are due to the presence of _______ carbonyl groups.

molecule

boiling point increases with an increase in the size of the ______.

Solubility

Smaller compounds are soluble in water as they are H-bond acceptors

Formaldehyde

- the simplest aldehyde

oxidation

methanol

Formaldehyde is manufactured on very large scale by the ______ of _____

Ag (Silver) catalyst

600-700°C

Formaldehyde catalyst at ___*C

formalin

Formaldehyde is supplied as a 37% aqueous solution called ___

it is used as a disinfectant and preservative

Formaldehyde

cold sterilant that effectively kills

all microorganisms, including spores and resistant viruses,

when used in proper concentrations and given adequate contact time.

Acetaldehyde

- manufactured mainly by the oxidation of ethylene

Palladium-copper (100-300°C)

Acetaldehyde catalyst at ___*C

4-hydroxy-3-methoxybenzaldehyde

Vanillin IUPAC name

Chanel No. 5

world's first abstract fragrance,

which incorporated more than 80

ingredients in a complex, multi-layered formulation process that uses aldehydes to heighten the scents

and give an airy nature to the floral notes.

Tolcapone

- adjunct therapy in the symptomatic

management of idiopathic Parkinson's disease.

✎ Suicidal drug

✎ Taken with Levodopa (Tolcapone + Levodopa)

Blood Brain Barrier (BBB)

Barrier preventing dopamine from entering the brain

Methadone

- opioid analgesic indicated for management of severe pain

that is not responsive to alternative

treatments

Glutaraldehyde

- primarily for disinfecting and sterilization of surfaces and equipment.

used as a cold sterilant

- disinfect a variety of heat-sensitive instruments:

- Endoscopes

- dialysis equipment

Voxelotor

- used to prevent the painful and

sometimes lethal vaso-occlusive crises associated with sickle

cell disease.

Aldehydes and ketones

Reduction of Carbonyl Compounds:

easily reduced to primary and secondary alcohols, respectively.

- lithium aluminum hydride (LiAlH4)

- sodium borohydride (NaBH4).

most common metal hydrides used to reduce carbonyl compounds (2)

aldehydes

Oxidation of Carbonyl Compounds:

Oxidation of ____ gives a carboxylic acid with the same number

of carbon atoms

1. KMnO4 (Potassium Permanganate)

2. CrO3 (Chromium trioxide)

3. Ag2O (Silver (I) oxide)

4. Peracids

Oxidizing agents: (4)

Jones reagent

- An aqueous solution of chromic acid

(H2CrO4).

Oxidizes: Secondary alcohol to Ketone

- chromium trioxide (CrO3)

- potassium dichromate (K2Cr2O7)

con'c H2SO4 followed by dilution with water and acetone.

Jones reagent prepared by dissolving:

Nucleophiles

Nucleophilic Addition Reactions:

attack the carbon atom of a

carbon-oxygen double bond because that carbon has a partial positive charge.

(Positive need niya negative)

- hydroxide ion

- hydride ion

- Carbanion

- alkoxide ion

- cyanide

Negatively charged nucleophiles: (5)

Tetrahedral intermediate

NUCLEOPHILIC ADDITION TO ALD/KET have two general variations:

protonated by water or acid to give an alcohol as the final product 2R-C-OH-Nu

carbonyl oxygen

NUCLEOPHILIC ADDITION TO ALD/KET have two general variations:

atom is protonated and then eliminated as HO- and H2O to give a

product with a R-C=Nu-R

Formation of Alcohols

carbon nucleophiles

Nucleophilic Addition Reactions:

Addition of Grignard Reagents: ___

Grignard reagents act as ____ toward

carbonyl compounds.

route

reaction of a Grignard reagent (RMgX) with a carbonyl compound provides a useful ____ to alcohols.

Primary Alcohols

Formaldehyde gives

Secondary Alcohol

Aldehyde give

Tertiary Alcohol

Ketones give

cyanohydrins

Nucleophilic Addition Reactions:

Addition of Hydrogen Cyanide:

Hydrogen cyanide adds to carbonyl group of aldehydes and ketones to form _____

Cyanohydrins

compounds with a hydroxyl and a cyano group attached to the same carbon

Arthur Lapworth

1900s

Studies of ____ in ___ showed that cyanohydrin formation is

REVERSIBLE and BASE-CATALYZED

ketals

Aldehydes and ketones react reversibly with 2 equivalents of an alcohol in the presence of an acid

catalyst to yield acetals, R2C(OR)2,

called as ____ if derived from ketone.

Hemiacetal

- contains both alcohol and ether

functional groups on the same carbon atom

- derived from an aldehyde

Acetals

two ether functions at the same carbon atom.

acetals

In the presence of excess alcohol:

- hemiacetals react further to form

Formation of Geminal Diols

Nucleophilic Addition Reactions

Addition of Water:

This is a reversible reaction

Geminal diols

- not stable and will lose the H2O to reform the more stable carbonyl group.

- is any org compound having 2 hydroxyl groups bound to the same carbon atom

Phenylhydrazine

- formerly used as antipyretic (Toxic effects on blood cells)

- is used as a chemical compound to induce anemia in animal studies