Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic...
Transcript of Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic...
![Page 1: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/1.jpg)
Oxidation And Reduction
Lecture-05
1Rahmana Emran / SF ITB
![Page 2: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/2.jpg)
1. Oxidation
• Oxidation is a reaction, during which the
average oxidation value of a compound
increases
• This can undergo due to:
Withdrawal of electrons
Withdrawal of hydrogen =
Dehydrogenation
Insertion of oxygen
2Rahmana Emran / SF ITB
![Page 3: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/3.jpg)
2. Reduction
• Reduction is a reaction, during which
the average oxidation value of a
compound decreases
• This can undergo due to:
Insertion of electrons
Insertion of hydrogen = hydrogenation
Withdrawal of oxygen
3Rahmana Emran / SF ITB
![Page 4: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/4.jpg)
3. The Oxidation Value in an Organic
Compound
• Determination of formal charge in three steps:
Step1: in a bond, all binding electrons are added to more electronegative partner
Step 2: in a bond of two identical bond partners, a half of the binding electrons are added to each bond partner
Step 3: Compare the sum of outside electrons of an atom in the compound with that of atom in question in elemental state
(Vergleich dieser Anzahl an Außenelektronen am Atom in der Verbindung mit der Anzahl der Außenelektronen des betreffenden Atoms im elementaren Zustand)
4Rahmana Emran / SF ITB
![Page 5: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/5.jpg)
Oxidation Values
5Rahmana Emran / SF ITB
![Page 6: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/6.jpg)
Oxidation Values of C-Atoms in
Different Compounds
6Rahmana Emran / SF ITB
![Page 7: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/7.jpg)
Titration of Diazo Dyes With Ti(III)
7Rahmana Emran / SF ITB
![Page 8: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/8.jpg)
Change in Oxidation Values
8Rahmana Emran / SF ITB
![Page 9: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/9.jpg)
PONCEAU 4R
N NS
S
HO
NaO
O
O
NaO
O
O
S
O
O
ONa
CLogP: 0.3888
9Rahmana Emran / SF ITB
![Page 10: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/10.jpg)
Reduction Products of
PONCEAU 4R
NH2H2N
S
S
HO
NaO
O
ONaO
O
O
S
O
O
ONa
CLogP: -2.152
CLogP: 0.117
10Rahmana Emran / SF ITB
![Page 11: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/11.jpg)
4. Oxidability (Oxidierbarkeit)
• Oxidability is the ability of a substance or a functional Group to be oxidized = Reducing ability
• A measure for the oxidability of functional group is the ionization potential, which can be polarographically determined (half wave potential). The measurement of ionization potential should be carried out to calculate the energy needed to abstract an electron from a substance
• The oxidability is a property of a substance. It depends not only from physical parameter, ionization potential, but also from chemical behavior, i.e. the reactivity against oxidizing agent
11Rahmana Emran / SF ITB
![Page 12: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/12.jpg)
Voltammogram of Fe
Fe(III) Fe(II) Fe(II) Fe
12Rahmana Emran / SF ITB
![Page 13: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/13.jpg)
5. Oxidation Reaction
• Alcohol, Aldehyd, Carboxylic Acid
• Chromate as oxidizing agent: Chrom(VI)-
Compounds (Chromates) in different solvents
are used
• Examples:
I. HCrO4 - in H2O: preparation: dissolve CrO3 in
H2O
II. CrO3 in acetone: Jones-Reagenz. Reaction:
Jones-Oxidation.
The basic reaction mechanism in the oxidation of
alcohols or aldehyds are as follows:13Rahmana Emran / SF ITB
![Page 14: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/14.jpg)
Oxidation of an Alcohol to Aldehyd or
Keton
14Rahmana Emran / SF ITB
![Page 15: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/15.jpg)
Oxidation of Aldehyd to Carboxylic
Acid
15Rahmana Emran / SF ITB
![Page 16: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/16.jpg)
Swern-Oxidation:
• The use of dimethylsulfoxide as Oxidizing
agent:
• The activation of DMSO:
Sulfonium-Ion Sulfonium-IonOxalylchloride 16Rahmana Emran / SF ITB
![Page 17: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/17.jpg)
Sulfonium-ion A and B are strong electrophiles and react in a
substitution reaction with alcohol to produce Sulfuran C.
Sulfuran
Dissoziation to sulfonium-ion D:
17Rahmana Emran / SF ITB
![Page 18: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/18.jpg)
Production of Sulfonium-Ylid E: CH acidity of Sulfonium-ion D
End step: Keton/Aldehid, under beta-elimination
via cyclic intermediate
18Rahmana Emran / SF ITB
![Page 19: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/19.jpg)
Oppenauer-Oxidation
Application: oxidation of steroid
19Rahmana Emran / SF ITB
![Page 20: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/20.jpg)
Mechanism1. Exchange of Ligand:
2. Reaction of Lewis Acid (Al-alcanolate) and Base
(Acetone), activated C-alpha:
20Rahmana Emran / SF ITB
![Page 21: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/21.jpg)
3. Hyride Shifting: from alcohol to activated alpha-C:
4. Dissoziation: release of oxidation product:
21Rahmana Emran / SF ITB
![Page 22: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/22.jpg)
3. Oxidation of Diol and
Olefin1. Epoxidation (Prileschaew-Reaction): electrophilic
Addition
22Rahmana Emran / SF ITB
![Page 23: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/23.jpg)
2. Lemieux-Johnson- und Malaprade-
Oxidation: Production of aldehyd from alkene
Mechanism of Lemieux-Johnson-Oxidation: 1. „Anlagerung“ of
osmium tetraoxide, 2. Hydrolisis
23Rahmana Emran / SF ITB
![Page 24: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/24.jpg)
2. Malaprada Oxidation:
24Rahmana Emran / SF ITB
![Page 25: Oxidation And Reduction - WordPress.comDec 05, 2010 · 3. The Oxidation Value in an Organic Compound • Determination of formal charge in three steps: Step1: in a bond, all binding](https://reader033.fdocuments.in/reader033/viewer/2022052813/6095ae79b9593400dd5b91c6/html5/thumbnails/25.jpg)
4. Oxidation of Keton to
EsterBaeyer-Villiger-Oxidation: 1. Addition of percarboxylic acid
to double bond, 2. Oxidation via cyclic intermediate
25Rahmana Emran / SF ITB