conversion of wedge - dash to fischer projection
DESCRIPTION
Conversion of wedge - dash to Fischer projection. The concepts deals with the conversion of the wedge dash representation of a given molecule in a Fischer projection. - PowerPoint PPT PresentationTRANSCRIPT
Conversion of wedge - dash to Fischer projection
The concepts deals with the conversion of the wedge dash representation of a given molecule in a Fischer projection
With the help of this animation user will be easily able to convert any molecule given in wedge dash representation to planer Fischer projection , hence will be able to study the stereochemistry of the given molecule
By Rachit AgarwalDepartment of chemistry
IIT Bombay
Master layout
Bond coming out of the plane
Bond on the plane
Bond going in the plane
R3
R2
R1R4
Carbon center
Here bond of C-R2 , C-R3 are in the plane , while of C-R1 is out of the plane and C-R4 inside the plane, the bond C-R4 is exactly behind the bond C-R1, but to show the C-R4 bond it is shown sidewaysR1 R2 R3 and R4 are general notation for the atom
wedge
dash
Wedge – dash representation
Beginner’s level
advance level
With two carbon center (red dots) H3C
CH3H2N
Cl
HO
H
H3C CH3
H H
HO
OH Cl
Cl
With three carbon center (red dots)
While looking the molecule from top or bottom the plane which is considered is of thickness T. In which the top layer passes through 2 carbon center and the lower layer through 1 carbon center
H3C CH3
H H
HO
OH Cl
Cl
T
Definition and rules for the users
There are certain rules that are to be followed while making the Fischer projection
Rule no 1) User should view the molecule from the same place while making the projection i.e. top right, top left, bottom right, bottom left
Rule no 2) In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Rule no 3) While rotating the bonds about any atom (chiral) the stereochemistry of the molecule does not changes
H3C
CH3H2N
Cl
HO
H
H3C CH3
H H
HO
OH Cl
Cl
Molecule with 2 chiral center
Molecule with 3 chiral center
Analogy / Scenario / Action / Example
3-D view of the given wedge dash molecule
3-D view of the molecule from a different angle so as to show all the atoms
The first 3-D molecule is rotated about the bond joining red and black atoms , such that orange atom comes out of the plane, green goes inside the plane and blue comes on the plane and the corresponding wedge – dash on the right side
R3
R2
R1R4
wedge – dash representation of the given molecule
R1
R2
R4R3
The heading over the slides (for user to understand)
There are total 8 types of option to be followed each containing of three (3) steps
The hierarch is shown below
Step 1
Action Description of the action Audio narration
Selection of the level Allow the user to click on one of two boxes containing the image with (option1 / option 2)
Select the level you want to learn, by clicking on desired box
Actual slide to be displayed
H3C
CH3H2N
Cl
HO
H H3C CH3
H H
HO
OH Cl
Cl
Select the level
For beginnersMolecule with two
carbon atom
For advanceMolecule with three
carbon atom
Option 1 Option 2
Step 2A
Action Description of the action Audio narration
Selection of the view point Allow the user to click on one of four boxes containing the view points i.e. top left, top right, bottom left, bottom right
Select the view point from which you would like to view the molecule
Actual slide to be displayed (option 1 selected)
H3C
CH3H2N
Cl
HO
H
Option 1
Select the view pointTop left Top right
bottom rightbottom left
Step 3AA
Actual slide to be displayed (top left view in option 1 selected)
CH3
CH3
ClH
NH2HO
TL2
CH3
CH3
HCl
NH2HO
TL3
CH3
CH3
NH2OH
HCl
TL4
H3C CH3
OH
H2N
H
Cl
TL1
Top left view
H3C
CH3H2N
Cl
HO
H
Top left viewCH3
CH3
NH2OH
HCl
Instruction on next slides
Initial display of the page final display of the page
H3C
CH3H2N
Cl
HO
H
TL0
Action Description of the action Audio narration
From TL0 to TL1
Rotate the molecule TL0 about the red line (axis) by 90 degrees toward yourself from top
From TL1 to TL2
Rotation the molecule TL1 by 90 degrees anti clock wise about the red spot
From TL2 to TL3
Rotate the bonds of TL2 molecule around the red spot (carbon atom) about the red axis by 180 degrees, for reference see the analogy slide
While rotating the bonds about any atom (chiral) the stereochemistry of the molecule does not changes
From TL3 to TL4
replace all the wedge and dash of TL3 molecule by simple lines and adjust the inclined bonds to become horizontal, so as to get the final image
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Step 3AA
CH3
CH3
NH2HO
HCl
BL4
H3C
CH3H2N
Cl
HO
H
BL0
H3C CH3
H2N
HO
Cl
H
BL1
CH3
CH3
HCl
OHH2N
BL2
Step 3AB
Actual slide to be displayed (bottom left view in option 1 selected)
bottom left view
H3C
CH3H2N
Cl
HO
H
Bottom left viewCH3
CH3
NH2OH
HCl
Instruction on next slides
Initial display of the page final display of the page
CH3
CH3
HCl
NH2HO
BL3
Action Description of the action Audio narration
From BL0 to BL1
Rotate the molecule BL0 about the red line (axis) by 90 degrees away from you from top
From BL1 to BL2
Rotation the molecule BL1 by 90 degrees anti clock wise about the red spot
From BL2 to BL3
Rotate the bonds of BL2 molecule around the red spot (carbon atom) about the red axis by 180 degrees, for reference see the analogy slide
While rotating the bonds about any atom (chiral) the stereochemistry of the molecule does not changes
From BL3 to BL4
replace all the wedge and dash of BL3 molecule by simple lines and adjust the inclined bonds to become horizontal, so as to get the final image
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Step 3AB
H3C CH3
OH
H2N
H
Cl
TR1
CH3
CH3
HOH2N
HCl
TR2
CH3
CH3
HOH2N
ClH
TR3
CH3
CH3
ClH
OHH2N
TR4H3C
CH3H2N
Cl
HO
H
TR0
Step 3AC
Actual slide to be displayed (top right view in option 1 selected)
Top right view
H3C
CH3H2N
Cl
HO
H
Top right view
Instruction on next slides
Initial display of the page final display of the page
CH3
CH3
ClH
OHH2N
Action Description of the action Audio narration
From TR0 to TR1
Rotate the molecule TR0 about the red line (axis) by 90 degrees towards yourself from top
From TR1 to TR2
Rotation the molecule TR1 by 90 degrees clock wise about the red spot
From TR2 to TR3
Rotate the bonds of TR2 molecule around the red spot (carbon atom) about the red axis by 180 degrees, for reference see the analogy slide
While rotating the bonds about any atom (chiral) the stereochemistry of the molecule does not changes
From TR3 to TR4
replace all the wedge and dash of TR3 molecule by simple lines and adjust the inclined bonds to become horizontal, so as to get the final image
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Step 3AC
H3C CH3
H2N
HO
Cl
H
BR1
CH3
CH3
NH2HO
ClH
BR2
CH3
CH3
HOH2N
ClH
BR3
CH3
CH3
ClH
OHH2N
BR4
H3C
CH3H2N
Cl
HO
H
BR0
Step 3AD
Actual slide to be displayed (bottom right view in option 1 selected)
Bottom right view
H3C
CH3H2N
Cl
HO
H
bottom right view
Instruction on next slides
Initial display of the page final display of the page
CH3
CH3
ClH
OHH2N
Action Description of the action Audio narration
From BR0 to BR1
Rotate the molecule BR0 about the red line (axis) by 90 degrees away from you from top
From BR1 to BR2
Rotation the molecule BR1 by 90 degrees clock wise about the red spot
From BR2 to BR3
Rotate the bonds of BR2 molecule around the red spot (carbon atom) about the red axis by 180 degrees, for reference see the analogy slide
While rotating the bonds about any atom (chiral) the stereochemistry of the molecule does not changes
From BR3 to BR4
replace all the wedge and dash of BR3 molecule by simple lines and adjust the inclined bonds to become horizontal, so as to get the final image
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Step 3AD
Step 2B
Action Description of the action Audio narration
Selection of the view point Allow the user to click on one of four boxes containing the view points i.e. top left, top right, bottom left, bottom right
Select the view point from which you would like to view the molecule
Actual slide to be displayed (option 2 selected)
Option 2
Select the view pointTop left Top right
bottom rightbottom left
H3C CH3
H H
HO
OH Cl
Cl
Step 3BA
Actual slide to be displayed (top left view in option 2 selected)
Top left view Top left view
Initial display of the page final display of the page
H3C CH3
H H
HO
OH Cl
Cl
HO Cl
HO H
Cl H
Continued on the next page ….
Top left view
Intermediate step
TLd1
H3C CH3
H H
HO
OH Cl
Cl
TLo
Cl OH
HO H
Cl H
TLb
HO Cl
H OH
H Cl
TLc
HO H
Cl H
TLd2
TLd1
HO Cl
HO H
Cl H
TLd3
H3C CH3
H H
HO
OH Cl
Cl
TLo
Cl
OH
OH
H
Cl
H
TLa
Instruction on next slide
Step 3BA
Action Description of the action Audio narration
Intermediate step appears
The fig in the intermediate steps will appear The basic Fischer diagram will be this , now we have to place the respective atoms
From TLo to TLa
Rotate the molecule Tlo about the red line (axis) by 90 degrees toward yourself from topNote: the TLd1 will remain as it is
From TLa to TLb Rotation the molecule TLa by 90 degrees anti clock wise about the red spot Note: the TLd1 will remain as it is
TLd1 to TLd2 TLd1 changes to TLd2 by placing the respective atoms
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
From TLb to TLc Rotate complete molecule about the red axis by 180 degreesNote: the TLd2 will remain as it is
By rotating the complete molecule about any axis the stereochemistry of the molecule does not changes
TLd2 to TLd3 TLd2 changes to TLd3 by placing the remaining respective atoms
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Step 3BA
Step 3BB
Actual slide to be displayed (bottom left view in option 2 selected)
bottom left view Bottom left view
Initial display of the page final display of the page
H3C CH3
H H
HO
OH Cl
Cl
HO Cl
HO H
Cl H
bottom left view
Intermediate step
H3C CH3
H H
HO
OH Cl
Cl
BLoBLd1
Continued on the next page ….
OH
Cl
H
OH
H
Cl
BLa
HO Cl
H OH
H Cl
BLb
HO Cl
HO H
Cl H
BLd3
H3C CH3
H H
HO
OH Cl
Cl
BLo
HO Cl
BLd2
BLd1
Cl OH
HO H
Cl H
BLc Instruction on next slides
Step 3BB
Action` Description of the action Audio narration
Intermediate step appears
The fig in the intermediate steps will appear The basic Fischer diagram will be this , now we have to place the respective atoms
From BLo to BLa
Rotate the molecule BLo about the red line (axis) by 90 degrees away from you from topNote: the TLd1 will remain as it is
From BLa to BLb Rotation the molecule BLa by 90 degrees anti clock wise about the red spot Note: the TLd1 will remain as it is
BLd1 to BLd2 BLd1 changes to BLd2 by placing the respective atoms
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
From BLb to BLc Rotate complete molecule about the red axis by 180 degreesNote: the BLd2 will remain as it is
By rotating the complete molecule about any axis the stereochemistry of the molecule does not changes
BLd2 to BLd3 BLd2 changes to BLd3 by placing the remaining respective atoms
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Step 3BB
TRd1
Step 3BC
Actual slide to be displayed (top right view in option 2 selected)
Top right view Top right view
Initial display of the page final display of the page
H3C CH3
H H
HO
OH Cl
Cl
H3C CH3
H H
HO
OH Cl
Cl
TRo
OHCl
OHH
ClH
Continued on the next page ….
Top right view
Intermediate step
Cl
OH
OH
H
Cl
H
TRa
ClHO
OHH
ClH
TRb
OHCl
HHO
HCl
TRc
OHCl
OHH
ClH
TRd3
Instruction on next slides
H3C CH3
H H
HO
OH Cl
Cl
TRo TRd1
OHH
ClH
TRd2
Step 3BC
Action` Description of the action Audio narration
Intermediate step appears
The fig in the intermediate steps will appear The basic Fischer diagram will be this , now we have to place the respective atoms
From TRo to TRa
Rotate the molecule TRo about the red line (axis) by 90 degrees towards yourself from topNote: the TRd1 will remain as it is
From TRa to TRb
Rotation the molecule TRa by 90 degrees clock wise about the red spot Note: the TRd1 will remain as it is
TRd1 to TRd2 TRd1 changes to TRd2 by placing the respective atoms
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
From TRb to TRc
Rotate complete molecule about the red axis by 180 degreesNote: the BLd2 will remain as it is
By rotating the complete molecule about any axis the stereochemistry of the molecule does not changes
TRd2 to TRd3 TRd2 changes to TRd3 by placing the remaining respective atoms
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Step 3BC
Step 3BD
Actual slide to be displayed (bottom right view in option 2 selected)
Bottom right view bottom right view
Initial display of the page final display of the page
H3C CH3
H H
HO
OH Cl
Cl
OHCl
OHH
ClH
H3C CH3
H H
HO
OH Cl
Cl
BRoBRd1
Continued on the next page ….
Top right view
Intermediate step
OH
Cl
H
OH
H
Cl
BRa
ClHO
OHH
ClH
BRc
OHCl
OHH
ClH
BRd3
Instruction on next slides
H3C CH3
H H
HO
OH Cl
Cl
BRo
OHCl
HHO
HCl
BRb
BRd1
OHCl
OHH
ClH
BRd2
Step 3BD
Step 3BD
Action` Description of the action Audio narration
Intermediate step appears
The fig in the intermediate steps will appear The basic Fischer diagram will be this , now we have to place the respective atoms
From BRo to BRa
Rotate the molecule BRo about the red line (axis) by 90 degrees away from you from topNote: the BRd1 will remain as it is
From BRa to BRb
Rotate the molecule BRa by 90 degrees clock wise about the red spot Note: the BRd1 will remain as it is
BRd1 to BRd2 BRd1 changes to BRd2 by placing the respective atoms
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
From BRb to BRc
Rotate complete molecule about the red axis by 180 degreesNote: the BRd2 will remain as it is
By rotating the complete molecule about any axis the stereochemistry of the molecule does not changes
BRd2 to BRd3 BRd2 changes to BRd3 by placing the remaining respective atoms
In Fischer projection the atoms/bonds which are in the horizontal line should come out of the plane while those are in vertical line should be going inside the plane
Links for further studies
Referencesbooks 1) Organic Chemistry Jonathan Clayden, Nick Greeves,
Stuart Warren, and Peter Wothers
2) Solomons, Fryhle: Organic Chemistry, 8th Edition
Websites 1) http://www.youtube.com/watch?v=KKOY1sdYEes
Questionnaire
Draw the Fischer of the following molecules
HO
H Cl
F OH
F I
Cl
HO
HF
H
A
C
B
D
Cl H
H
OHF
Answers
HO H
F H
D H
H Cl
HO F
HO F
Cl H
HO Cl
I F
A
C
B