Heartless boy in trouble backing African country (5)
I believe the answer is:
libya
'african country' is the definition.
(country in Africa)
'heartless boy in trouble backing' is the wordplay.
'heartless' says to hollow out the word (remove centre letters).
'in' is an insertion indicator.
'trouble' becomes 'ail' (synonyms).
'backing' shows that the letters should be reversed in order.
'boy' with its centre taken out is 'by'.
'ail' reversed gives 'lia'.
'by' placed into 'lia' is 'LIBYA'.
(Other definitions for libya that I've seen before include "North African country" , "Country in N. Africa" , "Tripoli's country" , "Assault; pester" , "North African republic" .)