Dodgy deal beside Sydney park for perfume chemical (8)

I believe the answer is:
aldehyde
'chemical' is the definition.
(I've seen this before)
'dodgy deal beside sydney park for perfume' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'deal' is 'alde' which is present in the answer.
'park' could be 'hyde' (I've seen this before) and 'hyde' is found within the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for aldehyde that I've seen before include "chemical" , "Organic compound" .)
