Hydroacylation is a type of organic reaction in which an aldehyde is added over an alkene or alkyne bond. The reaction product is a ketone. The reaction requires a metal catalyst and intramolecular reaction is favored over an intermolecular one. With alkynes the reaction product is an cyclopentenone.
The reaction was discovered by K. Sakai in 1972 as part in a synthetic route to certain prostanoids. The reagent in this reaction was tin tetrachloride. With an stoichiometric amount of Wilkinson's catalyst in chloroform, acetonitrile or benzene an equal amount of a cyclopropane was formed as the result of decarbonylation.
The first catalytic application was reported by Miller in 1976  in the reaction of 4-pentenal with Wilkinson's catalyst to form cyclopentanone. In this reaction the solvent was saturated with ethylene.
In a general reaction mechanism step one in hydroacylation is oxidative addition of the metal into the aldehyde carbon-hydrogen bond followed by side-on addition of the alkene, then followed by reductive elimination. A lurking side-reaction is decarbonylation from the acyl metal hydride RCH2(CO)MH to the alkane RCH3 and M(CO) via the RCH2M(CO)H intermediate.
Hydroacylation as an asymmetric reaction was first demonstrated by James and Young in 1983 (kinetic resolution)  and by Sakai in 1989 (true asymmetric synthesis)  both employing rhodium and a chiral diphosphine ligand. In one application the ligand is Me-DuPhos:
- Transition Metal Catalyzed Alkene and Alkyne Hydroacylation Michael C. Willis Chem. Rev. 2009 doi:10.1021/cr900096x
- Synthetic studies on prostanoids 1 synthesis of methyl 9-oxoprostanoate K. Sakai, J. Ide, O. Oda and N. Nakamura Tetrahedron Letters Volume 13, Issue 13, 1972, Pages 1287-1290 doi:10.1016/S0040-4039(01)84569-X
- Transition-metal-promoted aldehyde-alkene addition reactions Charles F. Lochow, Roy G. Miller J. Am. Chem. Soc., 1976, 98 (5), pp 1281–1283 doi:10.1021/ja00421a050
- The asymmetric cyclisation of substituted pent-4-enals by a chiral rhodium phosphine catalyst Brian R. James and Charles G. Young J. Chem. Soc., Chem. Commun., 1983, 1215 - 1216, doi:10.1039/C39830001215
- Catalytic decarbonylation, hydroacylation, and resolution of racemic pent-4-enals using chiral bis(di-tertiary-phosphine) complexes of rhodium(I) Brian R. James, and Charles G. Young Journal of Organometallic Chemistry Volume 285, Issues 1-3, 16 April 1985, Pages 321-332 doi:10.1016/0022-328X(85)87377-0
- Asymmetric cyclization reactions by Rh(I) with chiral ligands Yukari Tauraa, Masakazu Tanakaa, Kazuhisa Funakoshia and Kiyoshi Sakai Tetrahedron Letters Volume 30, Issue 46, 1989, Pages 6349-6352 doi:10.1016/S0040-4039(01)93891-2
- Asymmetric cyclization reactions. Cyclization of substituted 4-pentenals into cyclopentanone derivatives by rhodium(I) with chiral ligands Yukari Taura, Masakazu Tanaka, Xiao-Ming Wu, Kazuhisa Funakoshi and Kiyoshi Sakai Tetrahedron Volume 47, Issue 27, 1991, Pages 4879-4888 doi:10.1016/S0040-4020(01)80954-6
- Synthesis of D- and L-Carbocyclic Nucleosides via Rhodium-Catalyzed Asymmetric Hydroacylation as the Key Step Patricia Marce, Yolanda Dıaz, M. Isabel Matheu, and Sergio Castillon Org. Lett., 2008, 10 (21), pp 4735–4738 doi:10.1021/ol801791g