In bits when chloroformed? (7)

I believe the answer is:

asunder

I'm a little stuck... Click here to teach me more about this clue!

'in bits' is the definition.
(I've seen this before)

'when chloroformed?' is the wordplay.
'when' becomes 'as' (eg 'when I walked' means 'as I walked').
'chloroformed?' becomes 'under' (I can't justify this - if you can you should believe this answer much more).
'as'+'under'='ASUNDER'

Can you help me to learn more?

(Other definitions for asunder that I've seen before include "going to pieces" , "being in two" , "(Rent) apart" , "Widely separated" , "Apart - in pieces" .)

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.