Acetaldehyde, CH3CHO is considered prochiral because it can be converted into a chiral compound in a single step. Which of the following would cause acetaldehyde to form a chiral product?
A Addition of an -OH group
B Addition of an -H group
C Replacement of the C=O group with 2 -H groups
D Addition of an -OCH3 group
Addition of an -OCH3 group would make 4 different substituent groups on a carbon atom, making the molecule chiral. It would have a -CH3 group, an -OH group, an -H group, and an -OCH3 group. Options (A) through (C) would each result in the product having at least two identical substituents and therefore achiral.
The question I am wondering is why it is not A. Because the explanation for D makes it seems as if there should be a total of 8 Hydrogens after adding an OCH3 group because the explanation states it would have -CH3, -OH, -OCH3, and an -H group making 8 Hydrogens instead of 7 if you just add -OCH3 to CH3CHO.