Chiral Molecules - PowerPoint PPT Presentation

rodd
chiral molecules n.
Skip this Video
Loading SlideShow in 5 Seconds..
Chiral Molecules PowerPoint Presentation
Download Presentation
Chiral Molecules

play fullscreen
1 / 15
Download Presentation
Chiral Molecules
128 Views
Download Presentation

Chiral Molecules

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

  1. Chiral Molecules Chapter 12.6

  2. Definition of Isomer* Structural * Molecules with the same formula but different structure and characteristics Example C3H7OH 1-propanol 2-propanol

  3. Definition of Isomer * Stereoisomers/Enantiomers * Molecules that have the same structural components but are mirror images from each other Like left hand, right hand or right shoe, left shoe

  4. Enantiomers of Molecules They do not match up…no matter how they are rotated Rotated On Top

  5. Biological Importance • In the 3D environment of the body, enantiomers are considered two different molecules: only one version works! Like your right glove doesn’t fit your left hand

  6. Carbon Stereoisomers For carbon to form a stereoisomer – it has to bond to 4differentsubstituents Below: orange, purple, green and white

  7. Carbon Stereoisomer If Carbon does not have 4 different substituents, it can be rotated and made to overlap…giving an identical molecule

  8. Chirality A carbon with 4 different substituents is called a chiral carbon, often indicated by a * It can come in the form of two different enantiomers

  9. Fischer Projection Molecular drawing that shows chirality Chiral carbons are indicated as crosses SH SH H OH HO H NH2 NH2

  10. Fischer Projection Horizontal lines – forward bonds in 3-D model Vertical lines – bonds that point away in 3-D

  11. Mark all Carbons that are chiral

  12. Which of the molecules are correctly drawn as Fischer Projections? Yes 4 different substituents No – not chiral 2 OH attached to C No – not chiral 2 CHO attached to C ABC CHO COOH COH H3C H HO CH3 H3C OH CHO CHO OH

  13. Drawing Rules for Fischer Molecular axis has to be vertical with highest oxidized Carbon on top All chiral carbons become crossed lines Non-chiral carbons are written condensed Draw the molecule below as a Fischer Projection

  14. D and L Enantiomers The handedness of enantiomers is indicated as either L –Left or D- Right with reference to certain substituents

  15. D and L Enantiomers In larger carbohydrates, the hydroxyl furthest from the top is used for D and L