A2 ORGANIC

[kahynickel]

What is the logic behind the fact that ethanoyl chloride is more reactive than ethanoic acid?

 

[beacon_of_light]

Cl is a strong leaving group than OH ... And Carbon in ethanoyl chloride forms a strong electrophilic centre due to attachment to two electronegative atoms...

 

[kahynickel]

ethanoyl chloride vs ethanoci acid

this is one of the reasons. Whats the other.........................

 

[chemist12]

1st bond energy of C Cl i s 330 Kj while C O is 360, less energetic bond can easily broken, 2ndly bond between C and Cl is more polar (although Oxygen is more electronegative but Oxygen attract shared electron from both, C and H, while Cl only from C, So more polarize bond become weak)

 

[kahynickel]

C-Cl bond energy is not directly related here. Remember we are comparing ethanoyl chloride (CH3COCl) with ethanoic acid (CH3COOH). Cl is good leaving group in ethanoyl chloride BUT OH is bad leaving group in ethanoic acid We have to make OH a good leaving group i.e to convert it into a group which leave easily or spontaneously.

Now the other reason.........................

Take a look at the conjugate base of ethanoic acid and you will find the answer. (Rest to be done by you people)

 

[chemist12]

how we can decide, which group is good leaving group?? and why Cl is good as compared to OH ???Criteria ???