To do wrong with promises of money is nasty (6)
I believe the answer is:
odious
'nasty' is the definition.
(I've seen this before)
'to do wrong with promises of money' is the wordplay.
I cannot really see how this works, but
'promises' could be 'ious' (promises to pay a debt) and 'ious' is found within the answer.
'of' could be 'o' and 'o' is located in the answer.
A single letter 'd' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
'is' is the link.
Can you help me to learn more?
(Other definitions for odious that I've seen before include "Hateful and disgusting" , "Really hateful, abhorrent" , "Loathsome and repugnant" , "Loathsome and repulsive" , "Ghastly" .)