The configurations of the chirality centres i | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) To determine the configuration of the chirality centers in $D$-threose,we assign priorities to the groups attached to each chiral carbon using Cah

Vedclass · Accepted Answer

$2S, 3R$

Vedclass · Answer

(C) To determine the configuration of the chirality centers in $D$-threose,we assign priorities to the groups attached to each chiral carbon using Cahn-Ingold-Prelog $(CIP)$ rules.For $C-2$ (the chiral carbon attached to the $CHO$ group):$1$. $-OH$ (priority $1$)$2$. $-CH(OH)CH_2OH$ (priority $2$)$3$. $-CHO$ (priority $3$)$4$. $-H$ (priority $4$)In the Fischer projection,the $-H$ is on the horizontal bond. The sequence $1$ $\rightarrow 2$ $\rightarrow 3$ appears clockwise $(R)$,but since the lowest priority group $(-H)$ is on a horizontal bond,we reverse the configuration to $S$. Thus,$C-2$ is $2S$.For $C-3$ (the chiral carbon attached to the $CH_2OH$ group):$1$. $-OH$ (priority $1$)$2$. $-CHO$ (priority $2$)$3$. $-CH_2OH$ (priority $3$)$4$. $-H$ (priority $4$)In the Fischer projection,the $-H$ is on the horizontal bond. The sequence $1$ $\rightarrow 2$ $\rightarrow 3$ appears counter-clockwise $(S)$,but since the lowest priority group $(-H)$ is on a horizontal bond,we reverse the configuration to $R$. Thus,$C-3$ is $3R$.Therefore,the configuration is $2S, 3R$.

The configurations of the chirality centres in $D$-threose (shown) are

Similar Questions

$D$-glucose and $D$-fructose can be differentiated by

Lactose is composed of which of the following?

Which of the following does not show any reducing test of aldehyde?

The reaction of concentrated sulphuric acid with carbohydrates $(C_{12}H_{22}O_{11})$ is an example of

Glucose is a

Vedclass Test Series

Exam Paper Generator

Online Exam Module