PM's predecessor with chap in Middle East capital (5)
I believe the answer is:
amman
'middle east capital' is the definition.
(I've seen this before)
'pm's predecessor with chap' is the wordplay.
'pm's predecessor' becomes 'am' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'with' is a charade indicator (letters next to each other).
'chap' becomes 'man' (chap can mean a man).
'am'+'man'='AMMAN'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for amman that I've seen before include "City of Jordan" , "Jordanian capital" , "Jordan's capital" , "A capital f-fellow in Jordan?" , "Asian capital" .)