Hydroacylation is a type of organic reaction in which an electron-rich unsaturated hydrocarbon inserts into a formyl C-H bond.  With alkenes, the product is a ketone: 
:RCHO  +  CH=CHR   →   RC(O)CHCHR
With an alkyne instead, the reaction produces an α,β-unsaturated ketone.
The reaction requires a metal catalyst or a radical initiator.  It is almost invariably practiced as an intramolecular reaction using homogeneous catalysts, often based on rhodium phosphines.