# Reaction of 2,3-dichlorobutanoate with a decarboxylating agent followed by hydrochloric acid and then aq. potassium hydroxide

### Question

$$\ce{CH3-CH(Cl)-CH(Cl)-COO- ->[-CO2]A->[HCl]B->[aq KOH]C}$$ Product C is:

a) $$\ce{CH3-CH2-CHO}$$

b) $$\ce{CH3-CH(OH)-CH2-CH2-OH}$$

c) $$\ce{CH3-CHO}$$

d)$$\ce{CH3-C(=O)-CH3}$$

### My attempt

Where did I go wrong?

• the addition of HCL youve done to alkene is wrong , it will be geminal not vicinal there by making ans (a) Jul 27, 2020 at 17:36
• The answer is a) as long a propionaldehyde can avoid an aldol condensation in the presence of aqueous KOH. c) can't be the answer. Do the math on the number of carbons. Jul 27, 2020 at 19:17
• Yeah the answer is A my bad( i will edit it). But why where would the H+ attack(in the 2nd step)? I thought as i did because Cl- would make C+ unstable? Jul 28, 2020 at 5:00
• Also can someone advice me how to convert pictures to text like the above text ? I will try to make my questions better. Jul 28, 2020 at 5:01
• Shreya why would it be geminal ? Jul 28, 2020 at 20:56

the carbocation formed is more stable because of $$\ce{Cl}$$ +M.