title: Organic chemistry. Rh-catalyzed C-C bond cleavage by transfer hydroformylation.
abstract: The dehydroformylation of aldehydes to generate olefins occurs during the biosynthesis of various sterols, including cholesterol in humans. Here, we implement a synthetic version that features the transfer of a formyl group and hydride from an aldehyde substrate to a strained olefin acceptor. A Rhodium (Xantphos)(benzoate) catalyst activates aldehyde carbon-hydrogen (C-H) bonds with high chemoselectivity to trigger carbon-carbon (C-C) bond cleavage and generate olefins at low loadings (0.3 to 2 mole percent) and temperatures (22° to 80°C). This mild protocol can be applied to various natural products and was used to achieve a three-step synthesis of (+)-yohimbenone. A study of the mechanism reveals that the benzoate counterion acts as a proton shuttle to enable transfer hydroformylation.
authors.affiliation: Department of Chemistry, University of California Irvine, CA 92697-2025, USA. Department of Chemistry, University of Toronto, Ontario M5S 3H6, Canada.
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Murphy
authors.affiliation: Department of Chemistry, University of California Irvine, CA 92697-2025, USA.
authors.forename: Jung-Woo
authors.initials: JW
authors.lastname: Park
authors.affiliation: Department of Chemistry, University of California Irvine, CA 92697-2025, USA.
authors.forename: Faben A
authors.initials: FA
authors.lastname: Cruz
authors.affiliation: Department of Chemistry, University of California Irvine, CA 92697-2025, USA. dongv@uci.edu.
authors.forename: Vy M
authors.initials: VM
authors.lastname: Dong
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D000475:Alkenes / Q000138:chemical synthesis*; D001688:Biological Products / Q000138:chemical synthesis*; D002384:Catalysis; D006860:Hydrogen Bonding; D012238:Rhodium / Q000737:chemistry*
chemical_list: D000447:Aldehydes; D000475:Alkenes; D001688:Biological Products; D012238:Rhodium