Conversion of wedge - dash to Fischer projection

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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 Agarwal Department of chemistry IIT
Bombay
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Master layout
Beginners level
wedge
With two carbon center (red dots)
advance level
With three carbon center (red dots)
dash
Wedge dash representation
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
Carbon center
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Definition and rules for the users
Molecule with 2 chiral center
Molecule with 3 chiral center
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
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Analogy / Scenario / Action / Example
3-D view of the molecule from a different angle
so as to show all the atoms
3-D view of the given wedge dash molecule
wedge dash representation of the given molecule
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
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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
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Step 1
Actual slide to be displayed
Select the level
Option 1
Option 2
For beginners Molecule with two carbon atom
For advance Molecule with three carbon atom
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
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Step 2A
Actual slide to be displayed (option 1 selected)
Select the view point
Option 1
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
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Step 3AA
Actual slide to be displayed (top left view in
option 1 selected)
Initial display of the page
final display of the page
Instruction on next slides
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Step 3AA
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
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Step 3AB
Actual slide to be displayed (bottom left view in
option 1 selected)
Initial display of the page
final display of the page
Instruction on next slides
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Step 3AB
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
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Step 3AC
Actual slide to be displayed (top right view in
option 1 selected)
Initial display of the page
final display of the page
Instruction on next slides
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Step 3AC
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
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Step 3AD
Actual slide to be displayed (bottom right view
in option 1 selected)
Initial display of the page
final display of the page
Instruction on next slides
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Step 3AD
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
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Step 2B
Actual slide to be displayed (option 2 selected)
Select the view point
Option 2
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
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Step 3BA
Actual slide to be displayed (top left view in
option 2 selected)
Initial display of the page
final display of the page
Intermediate step
Continued on the next page .
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Step 3BA
Instruction on next slide
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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 top Note 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 degrees Note 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
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Step 3BB
Actual slide to be displayed (bottom left view in
option 2 selected)
Initial display of the page
final display of the page
Intermediate step
Continued on the next page .
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Step 3BB
Instruction on next slides
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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 top Note 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 degrees Note 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
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Step 3BC
Actual slide to be displayed (top right view in
option 2 selected)
Initial display of the page
final display of the page
Intermediate step
Continued on the next page .
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Step 3BC
Instruction on next slides
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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 top Note 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 degrees Note 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
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Step 3BD
Actual slide to be displayed (bottom right view
in option 2 selected)
Initial display of the page
final display of the page
Intermediate step
Continued on the next page .
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Step 3BD
Instruction on next slides
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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 top Note 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 degrees Note 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
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Links for further studies
References
books 1) Organic Chemistry Jonathan Clayden, Nick Greeves, Stuart Warren, and Peter Wothers 2) Solomons, Fryhle Organic Chemistry, 8th Edition
Websites http//www.youtube.com/watch?vKKOY1sdYEes
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Questionnaire
Draw the Fischer of the following molecules
A
B
C
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Answers
A
B
C