ALKENES.

Slides:



Advertisements
Similar presentations

Advertisements

4-1 © 2005 John Wiley & Sons, Inc All rights reserved Chapter 4: Alkenes and Alkynes.
1 Alkenes. 2 Alkanes:C n H 2n+2 saturated hydrocarbons Alkenes:C n H 2n unsaturated hydrocarbons ethene (ethylene) propene (propylene) 2-methylpropene.
ORGANIC CHEMISTRY HYDROCARBONS Examples of Alkenes ETHENE, C 2 H 4 H C C H OR CH 2 CH 2 PROPENE CH 2 CH CH 3 TASK: Use ball & stick models or sketches.
Alkenes C n H 2n “unsaturated” hydrocarbons C 2 H 4 ethylene Functional group = carbon-carbon double bond sp 2 hybridization => flat, 120 o bond angles.
20.7 Naming Alkenes & Alkynes Alkene formula = C n H 2n Alkyne formula = C n H 2n-2 geometric isomers cis-2-butenetrans-2-butene.
By: Dr. Siham Lahsasni 1 Unsaturated Hydrocarbons 1 Alkenes.
Alkenes and alkynes The chemistry of unsaturation.
LecturePLUS Timberlake1 Alkenes and Alkynes Geometric Isomers of Alkenes Addition Reactions.
© E.V. Blackburn, 2011 Alkenes C n H 2n. © E.V. Blackburn, 2011 Alkenes called unsaturated hydrocarbons also known as olefins (oleum, latin, oil; facere,
Chapter 6 Alkenes and Alkynes I: Structure and Preparation
Unsaturated Hydrocarbons
Unsaturated Hydrocarbons
Unsaturated Hydrocarbons: Alkenes 108 Chem Chapter 3 1.
Ch. 12 Alkenes Homework , 12.17, 12.19, 12.23, 12.25, 12.27, 12.36, 12.37, 12.41,12.42, 12.43,
5.1 Alkene Nomenclature. Alkenes Alkenes are hydrocarbons that contain a carbon-carbon double bond also called "olefins" characterized by molecular formula.
Unsaturated Hydrocarbons
Nomenclature- Alkenes and Alkynes. Alkenes and Alkynes Unsaturated ◦ contain carbon-carbon double and triple bond to which more hydrogen atoms can be.
Alkenes and Alkynes Geometric Isomers of Alkenes Addition Reactions.
Unsaturated Hydrocarbons Alkenes CHEMISTRY 11 MS. MCGRATH.
1. The ene suffix (ending) indicates an alkene 2. The longest chain chosen for the root name must include both carbon atoms of the double bond. 3. The.
Alkenes - Synthesis and Reactions
CONCURRENT ENROLLMENT
Saturated and Unsaturated Hydrocarbons
Chapter 3 ALKENES Dr. Yasser Mostafa Abdallah
Alkenes CnH2n “unsaturated” hydrocarbons
Chapter 23: Organic Chemistry
Chapter 7 Alkenes and Alkynes I: Properties and Synthesis Elimination Reactions of Alkyl Halides.
Alkenes CnH2n.
Naming Hydrocarbons.
Simple Organic Chemistry
Unsaturated Hydrocarbons
Isomers & Functional Groups
Ch #12 Alkenes and Alkynes.
Alcohols د. جهاد الماليطي.
9/16/2018 CHEM 244 PRINCIPLES OF ORGANIC CHEMISTRY I FOR CHEMICAL ENGINEERING’ STUDENTS, COLLEGE OF ENGINEERING PRE-REQUISITES COURSE; CHEM 101 CREDIT.
Alkynes Dr Seemal Jelani Chem-160 9/16/2018.
Chapt 21 Hydrocarbons [Selected]
Introduction Most of the advances in the pharmaceutical industry are based on a knowledge of organic chemistry. Many drugs are organic compounds.
Saturated Hydrocarbons: Alkanes
biology…is that everything that animals do,
Simple Organic Chemistry Basic Structure and Nomenclature
Alkenes, Cycloalkenes and Dienes
Chapter 3: Alkenes and Alkynes
Alkanes Notes by OnyangoNgoye.
Chapter 7 Alkenes and Alkynes I: Properties and Synthesis Elimination Reactions of Alkyl Halides.
CH 7-2: Alkene & Alkyne Nomenclature
Organic Compounds (Part 2)
Unsaturated Hydrocarbons
Chapter 3 Adel M. Awadallah Islamic University of Gaza
Unsaturated Hydrocarbons II: Dienes and Alkynes
Unsaturated Hydrocarbons II: Dienes and Alkynes
Drill: Draw & Name Reactants & Products
Nomenclature of Alkenes
Fundamentals of Organic Chemistry
Alkenes & Alkynes.
Unsaturated Hydrocarbons: Alkenes
Synthesis and Properties of Alkene and Alkynes
Alkenes and Alkynes Learning Objectives: Keywords:
Fundamentals of Organic Chemistry
Alkynes. CnH2n-2 C2H2 H:C:::C:H H—C  C—H sp => linear, 180o
Synthesis and Properties of Alkene
Alkynes. CnH2n-2 C2H2 H:C:::C:H H—C  C—H sp => linear, 180o
Synthesis and Properties of Alkene
LATE ABASAHEB KAKADE ART’S & SCIENCE COLLEGE , BODHEGAON
Simple Organic Chemistry
Schedule Today (4/17): Chapter 21 Friday (4/19): Chapter 21
Synthesis and Properties of Alkene and Alkynes
Important Alkenes in Nature
Synthesis and Properties of Alkene and Alkynes
Presentation transcript:

ALKENES

Alkenes CnH2n “unsaturated” hydrocarbons C2H4 ethylene Functional group = carbon-carbon double bond

C3H6 propylene C4H8 butylene CH3CH=CHCH3 β-butylene isobutylene 2-butene 2-methylpropene

there are two 2-butenes: cis-2-butene trans-2-butene Diastereomers

C=C are called “vinyl” carbons If either vinyl carbon is bonded to two equivalent groups, then no geometric isomerism exists. CH3CH=CHCH3 CH3CH2CH=CH2 yes no CH3 (CH3)2C=CHCH3 CH3CH=CCH2CH3 no yes

E/Z system is recommended by IUPAC for the designation of geometric isomerism. Use the sequence rules to assign the higher priority * to the two groups attached to each vinyl carbon. 2. * * * * (Z)- “zusammen” (E)- “entgegen” together opposite

* * (Z)- (E)- * *

Nomenclature, alkenes: Parent chain = longest continuous carbon chain that contains the C=C. alkane => change –ane to –ene prefix a locant for the carbon-carbon double bond using the principle of lower number. Similar to alkanes If a geometric isomer, use E/Z (or cis/trans) to indicate which isomer it is.

* * * * (Z)-3-methyl-2-pentene (3-methyl-cis-2-pentene) (E)-1-bromo-1-chloropropene *

CH3 CH3CH2 CHCH2CH3 \ / C = C 3-ethyl-5-methyl-3-heptene / \ CH3CH2 H (not a geometric isomer)

-ol has the priority when naming CH2=CHCH2-OH 2-propen-1-ol CH3CHCH=CH2 3-buten-2-ol OH

Physical properties: non-polar or weakly polar no hydrogen bonding low mp/bp similar to alkanes Insoluble in water Importance: common group in biological molecules

Preparation of alkenes: dehydrohalogenation of alkyl halides 2. dehydration of alcohols dehalogenation of vicinal dihalide

2. dehydration of alcohols

dehydrohalogenation of alkyl halides | | | | — C — C — + KOH(alc.)  — C = C — + KX + H2O | | H X

dehalogenation of vicinal dihalides | | | | — C — C — + Zn  — C = C — + ZnX2 | | X X eg. CH3CH2CHCH2 + Zn  CH3CH2CH=CH2 + ZnBr2 Br Br

R-OH H+ R-X KOH Alkene (alc.) Zn vicinal dihalide

Reduction of alkynes

Reactions of Alkenes Addition of hydrogen

Addition of halogens

Addition of hydrogen halides

Addition of hydrogen halides

Additon of water

Halohydrin formation

Dimerization

Alklyation

Oxymercuration-Demercuration

Hydroboration-Oxidation

Polymerization

Hydroxylation