Question

Match the Column (I) and Column (II).(Matrix)

	Column (I) Molecule		Column (II) Configuration
(a)		(p)	R-(Rectus)
(b)		(q)	S-(Sinister)
(c)		(r)	D
(d)		(s)	L

• A. $a\to p,r;b\to q,s;c\to q,s;d\to p,r$
• B. $a\to q,r;b\to p,s;c\to q,s;d\to p,r$
• C. $a\to p,r;b\to r,s;c\to q,s;d\to p,q$
• D. $a\to p,r;b\to q,s;c\to q,r;d\to p,s$

Answer 1

The correct option is D $a\to p,r;b\to q,s;c\to q,r;d\to p,s$

$R-S$ configuration in Fischer projection: If the $4^{th}$ priority is on the vertical line, the clockwise rotation is $R$ and anticlockwise rotation is $S.$ On the other hand, ff the $4^{th}$ priority is on the horizontal line, the clockwise rotation is $S$ and anticlockwise rotation is $R.$

$D$ and $L$ configuration: Write the molecule in such a way that most oxidised carbon $CHO$ or $COOH$ is at top vertical position. If the $OH$ or $N{H}_2$ group present at the lowest chiral carbon atom is on the left hand side then it assign it as $L$ configuration and if it is on the right hand side then assign it as $D$ configuration.