Table of contents  
Sawhorse Representation  
Newman Projection  
Fischer Projection (2D representation)  
Flying–Wedge Representation (3D representation)  
Interconversions 
The sawhorse formula indicates the spatial arrangement of all the groups on two adjacent carbon atoms is represented by a diagonal line usually from lower left to upper right.
The Newman projection formula is the planar projection formula of the sawhorse formula.
The Fischer projection, devised by Emil Fischer in 1891, is a twodimensional representation of a threedimensional organic molecule by projection.
In order to find out whether the two structures are identical or not, these projections can be manipulated only in specific ways. The following rules must be obeyed.
1. For comparison, a Fischer projection may be rotated 180° in the plane of the paper & molecule remains the same.
2. One interchange in the Fischer projection leads to the enantiomers. Configuration at the
stereocenter changes from (S) to (R) and viceversa.
3. Two or any even number of interchanges of the groups at the chiral center, don’t change the configuration.
4. A 90^{0} rotation of the Fischer projection formula about the chiral center inverts the configuration.
5. It is not permitted to lift projection formulae out of the plane of the paper and flip them over or view them from the opposite side of the paper. These operations, if done, are the same as breaking a bond to change the configuration of the original molecule.
For Example:
6. Fischer projection can be manipulated by rotating a group of any three ligands in a clockwise or anticlockwise direction; the fourth ligand doesn’t change its position (Such a manipulation is equivalent to two interchanges).
The FlyingWedge Projection is the most widely used threedimensional representation of a molecule on a twodimensional surface (paper).
This kind of representation is usually done for a molecule containing a chiral center. In this type of representation, three types of lines are used.
i. Eclipsed conformation (Flying wedge projection).
ii. Eclipsed conformation (Fischer projection).
iii. Staggered conformation (Flying wedge projection).
Sawhorse into Fischer Conversion
Conversion of Fischer Projection into Sawhorse Projection via Newmann Projection
35 videos92 docs46 tests

1. What is the purpose of using Sawhorse, Newman, Fischer Projections in organic chemistry? 
2. How do you convert a Sawhorse Projection to a Newman Projection? 
3. What is the advantage of using Fischer Projections over other types of molecular representations? 
4. How do you interconvert Fischer and Newman Projections? 
5. Can you provide an example of when using FlyingWedge Representation is more beneficial than other types of molecular representations? 

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