What is the difference between oxo and formyl? both represent aldehyde when used as a substituent(correct me if I am wrong). But when should I use formyl and when oxo?
This answers my problem and also says that oxo is also used for aldehyde.
If they get priority in the name they get the suffix ‘al’ or ‘carbaldehyde’ As substituent prefixes ‘oxo’ and ‘formyl’ are used. The prefix ‘formyl’ is used in preferred IUPAC names, except for a -CHO group at the end of an acyclic chain.
However he did not give any sources.