1 / 9

Geometric ISOMERS of Alkenes

Geometric ISOMERS of Alkenes. Chapter 12 Section 3. ALKENES. The CARBON – CARBON double bond is rigid (no free rotation) because of the shapes of the orbitals involved in its formation Pi bond Sigma bond 2 p-orbital electrons the electrons lie l ie above and below in a line between

berne
Download Presentation

Geometric ISOMERS of Alkenes

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Geometric ISOMERS of Alkenes Chapter 12 Section 3

  2. ALKENES The CARBON – CARBON double bond is rigid (no free rotation) because of the shapes of the orbitals involved in its formation Pi bondSigma bond 2 p-orbital electrons the electrons lie lie above and below in a line between the 2 carbons the 2 carbon nuclei Rotation around the double bond is restricted because the pi bond would have to be broken to allow for rotation. THUS, THE DOUBLE BOND IS RIGID

  3. Geometric Isomers In cycloalkanes,cis/trans applied to the branches trans = on OPPOSITE sides of the ring cis = on the SAME side of the ring

  4. Geometric Isomers In alkenes, cis/trans applies to the location of the parent chain around the double bond, NOT the branches

  5. Geometric Isomers If one of the carbons of the double bond has 2 identical substituents there are NO cis/trans isomers.

  6. Example: 1,1-dichloroethene nocis/trans because both carbons have identical substituents 1,2-dichloroethene cis/trans isomers DO exist in this molecule

  7. Which exist as geometric isomers? 1-pentene 3-ethyl-3-hexene 3-methyl-2-pentene

  8. Draw these molecules. Cis-3-octene Trans-5-chloro-2-hexene Trans-2,3-dichloro-2-butene

  9. HOMEWORK 3RD EDITION: P351 #19, 23, 24, 26 4TH EDITION: P359 #21, 25, 26, 28

More Related