Advices For Studying Organic Chemistry

1) Only one compound with the general formula CH 3 X is ever found.

2) Only one compound with the formula CH 2 X 2 or CH 2 XY is ever found.

3) Two enantiomeric compounds with the formula CHXYZ are found.

H

HH

H

C H

H H

C H H

H H

H

C

Planar Pyramidal Tetrahedral

H

HH

X C H X

HH

C Y

H Y

C H

Cis Trans

Cis Trans

X X

H H

C Y H

H H

C H

H Y

C H

YX H X

H

C H Y

H

rotate 180 C

o

Y

X Z X

H

C Z Y

H

C

5.5 TESTS FOR CHIRALITY: PLANES OF SYMMETRY

1. Superposibility of the models of a molecule and its mirage:
   
   
   1. If the models are superposable, the molecule that they represent is achiral.
   
   
   2. If the models are nonsuperposable, the molecules that they represent are chiral.
   
   
   
   


2. The presence of a single tetrahedral stereocenter ⇒ chiral molecule.


3. The presence of a plane of symmetry ⇒ achiral molecule
   
   
   1. A plane of symmetry (also called a mirror plane) is an imaginary plane that
      bisects a molecule in such a way that the two halves of the molecule are mirror