slide1
Download
Skip this Video
Download Presentation
Aldehydes and Ketones

Loading in 2 Seconds...

play fullscreen
1 / 41

Aldehydes and Ketones - PowerPoint PPT Presentation


  • 177 Views
  • Uploaded on

Aldehydes and Ketones. Before you can learn about aldehydes and ketones, you must first know something about the nomenclature of carboxylic acids since many of the names of aldehydes and ketones are derived from the names of the corresponding carboxylic acids. Carboxylic acids:

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Aldehydes and Ketones' - dexter-bennett


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide2

Before you can learn about aldehydes and ketones, you must first know something about the nomenclature of carboxylic acids since many of the names of aldehydes and ketones are derived from the names of the corresponding carboxylic acids.

slide3

Carboxylic acids:

R-COOH, R-CO2H,

Common names:

HCO2H formic acid L. formica ant

CH3CO2H acetic acid L. acetum vinegar

CH3CH2CO2H propionic acid G. “first salt”

CH3CH2CH2CO2H butyric acid L. butyrum butter

CH3CH2CH2CH2CO2H valeric acid L. valerans

slide4

Carboxylic acids, common names:

CH3(CH2)4CO2H caproic acid L. caper goat

CH3(CH2)5CO2H ---

CH3(CH2)6CO2H caprylic acid

CH3(CH2)7CO2H ---

CH3(CH2)8CO2H capric acid

CH3(CH2)9CO2H ---

CH3(CH2)10CO2H lauric acid oil of lauryl

slide5

5 4 3 2 1

C—C—C—C—C=O

δ γ β α used in common names

slide7

ALDEHYDES AND KETONES

“carbonyl” functional group:

Aldehydes Ketones

slide8

Nomenclature:

Aldehydes, common names:

Derived from the common names of carboxylic acids;

drop –ic acid suffix and add –aldehyde.

CH3

CH3CH2CH2CH=O CH3CHCH=O

butyraldehyde isobutyraldehyde

(α-methylpropionaldehyde)

slide10

Aldehydes, IUPAC nomenclature:

Parent chain = longest continuous carbon chain containing the carbonyl group; alkane, drop –e, add –al. (note: no locant, -CH=O is carbon #1.)

CH3

CH3CH2CH2CH=O CH3CHCH=O

butanal 2-methylpropanal

H2C=O CH3CH=O

methanal ethanal

slide11

Ketones, common names:

Special name:acetone

“alkyl alkyl ketone” or “dialkyl ketone”

slide12

(o)phenones:

Derived from common name of carboxylic acid, drop –ic acid, add –(o)phenone.

slide13

Ketones: IUPAC nomenclature:

Parent = longest continuous carbon chain containing the carbonyl group. Alkane, drop –e, add –one. Prefix a locant for the position of the carbonyl using the principle of lower number.

slide14

Physical properties:

polar, no hydrogen bonding

mp/bp are relatively moderate for covalent substances

water insoluble

(except: four-carbons or less)

slide15

Spectroscopy:

IR: C=O stretch, strong ~1700 cm-1

RCHO 1725 ArCHO 1700

R2CO 1710 ArCOR 1690

C—H stretch for aldehydes 2720

nmr: -CHO 9-10 ppm

slide16

acetophenone

C=O

stretch

slide17

valeraldehyde

CHO

C—H

stretch

2720 cm-1

C=O stretch

slide18

valeraldehyde

CH3CH2CH2CH2CH=O

a b c d e

-CHO

slide19

Oxidation/Reduction:

oxidation numbers:

oxidation

-4 -2 0 +2 +4

CH4 CH3OH H2C=O HCO2H CO2

alkane alcohol aldehyde carboxylic acid

reduction

slide20

Aldehydes, syntheses:

  • Oxidation of 1o alcohols
  • Oxidation of methylaromatics
  • Reduction of acid chlorides
  • Ketones, syntheses:
  • Oxidation of 2o alcohols
  • Friedel-Crafts acylation
  • Coupling of R2CuLi with acid chloride
slide21

Aldehydes synthesis 1) oxidation of primary alcohols:

RCH2-OH + K2Cr2O7, special conditions  RCH=O

RCH2-OH + C5H5NHCrO3Cl  RCH=O

(pyridinium chlorochromate)

[With other oxidizing agents, primary alcohols  RCOOH]

slide28

Ketone synthesis: 2) Friedel-Crafts acylation

Aromatic ketones (phenones) only!

slide33

Aldehydes, syntheses:

  • Oxidation of 1o alcohols
  • Oxidation of methylaromatics aromatic only
  • Reduction of acid chlorides
  • Ketones, syntheses:
  • Oxidation of 2o alcohols
  • Friedel-Crafts acylation aromatic only
  • Coupling of R2CuLi with acid chloride
slide34

K2Cr2O7, special cond.

or C5H5NHCrO3Cl

1o alcohol

Ar-CH3

CrO3 H2O

(AcO)2O

aldehyde

acid chloride

LiAlH(O-t-Bu)3

slide35

2o alcohol

NaOCl, etc.

ketone

acid chloride + ArH

AlCl3

acid chloride + R2CuLi

slide36

outline three different syntheses for benzaldehyde

  • outline three different syntheses for benzophenone
  • outline a different synthesis for each of the following compounds:
  • cyclohexanone, 4-bromobenzaldehyde, 2-pentanone, valeraldehyde, acetophenone, isobutyraldehyde,
slide39

cyclohexanone, 4-bromobenzaldehyde, 2-pentanone, valeraldehyde, acetophenone, isobutyraldehyde, using a different method for each one.

ad