Question

$D (-)-$ Threose $\longrightarrow { NaBH _{4}}{\longrightarrow }( R )$
$D (-)-$ Erythrose $\stackrel{ NaBH _{4}}{\longrightarrow }( P )$
Which of the following statement is correct about P and R?

• A. Both are optically active
• B. Both are optically inactive
• C. P is optically inactive and R is optically active
• D. Neither P nor R has asymmetric carbon

Answer 1

Answer: (C)

P is optically inactive as it contains the center of symmetry and R is optically active as it contains no element of symmetry.