Paul -, crooner of the 1950s hits Diana and Lonely Boy (4)

'paul crooner of the 1950s hits' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'and lonely boy' is the wordplay.
I cannot really understand how this works, but
'and' could be 'n' (common abbreviation for 'and') and 'n' is found within the answer.
The remaining letters 'aka' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...

'diana' acts as a link.

Can you help me to learn more?