Question

How do you draw a ($2R$, $3R$)$- 2,3 - dichloropentane$?

Answer 1

Both $Cl$ groups ought to point in reverse. In the wake of relegating needs, the rotation of this will be like counter-clock wise (which implies $S$) anyway in light of the fact that the most priority group is pointing in reverse, the $S$ becomes $R$.

Complete step by step answer:
The structure is beneath...

- $Molecular{\text{ }}Formula \to {C_5}{H_{10}}C{l_2}$
- $Average{\text{ }}mass \to 141.039Da$
- $Monoisotopic{\text{ }}mass \to 140.015961{\text{ }}Da$
Draw the structure of ($2R$, $3R$)$- 2,3 - dichloropentane$. Utilize strong or hashed wedges to demonstrate the setup at uneven $C$ atoms. Draw the molecule on the image by selection fasteners from the Tools (for bonds), Atoms, and Innovative Template toolbars. The single bond is dynamic as a matter of course. Show the suitable stereochemistry by picking the ruined or obstructed buttons and afterward clicking a bond on the canvas.
The guidelines have developed to cover numerous circumstances; however, the essential principles are:
Think about the main atom of each piece of the molecule. An atom with higher atomic number has higher need. (for example, $I{\text{ }} > {\text{ }}Cl{\text{ }} > {\text{ }}C{\text{ }} > {\text{ }}H$). On the off chance that the principal atom of two groups is the equivalent, consider the second atom(s) similarly as the first. (for example, $- C{\left( {C{H_3}} \right)_3}\; > {\text{ }} - CH{\left( {C{H_3}} \right)_2}\; > {\text{ }} - C{H_2}C{H_3}\; > {\text{ }} - C{H_3}$). On the off chance that this doesn't allocate need, consider the following atoms until there is a distinction.

$R -$ and $S -$ documentation utilize the CIP need rules for the task of the supreme design around a stereocenter. To start with, appointment needs as portrayed above to each bonded bunch encompassing the stereocenter ($1$, most noteworthy to$4$, least). Second, point the least needed ($4$) atom away from you. Follow the heading of the leftover $3$ needs from most elevated to least needed (most reduced to most noteworthy number, $1 < 2 < 3$).

Note:
Stereoisomers are appropriately named utilizing the Cahn-Ingold-Prelog (CIP) need rules to choose which parts of the molecule to think about first. A counterclockwise bearing is a $S$ (sinister, Latin for left) arrangement. A clockwise heading is a $R$ (rectus, Latin for right) setup.