title: Highly enantioselective rhodium(I)-catalyzed carbonyl carboacylations initiated by C-C bond activation.
abstract: The lactone motif is ubiquitous in natural products and pharmaceuticals. The Tishchenko disproportionation of two aldehydes, a carbonyl hydroacylation, is an efficient and atom-economic access to lactones. However, these reaction types are limited to the transfer of a hydride to the accepting carbonyl group. The transfer of alkyl groups enabling the formation of CC bonds during the ester formation would be of significant interest. Reported herein is such asymmetric carbonyl carboacylation of aldehydes and ketones, thus affording complex bicyclic lactones in excellent enantioselectivities. The rhodium(I)-catalyzed transformation is induced by an enantiotopic CC bond activation of a cyclobutanone and the formed rhodacyclic intermediate reacts with aldehyde or ketone groups to give highly functionalized lactones.
authors.affiliation: Laboratory of Asymmetric Catalysis and Synthesis, EPFL SB ISIC LCSA, BCH 4305, 1015 Lausanne (Switzerland) http://isic.epfl.ch/lcsa.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Souillart
authors.forename: Nicolai
authors.initials: N
authors.lastname: Cramer
mesh_terms: D000215:Acylation; D000447:Aldehydes / Q000737:chemistry; D000475:Alkenes / Q000737:chemistry*; D002384:Catalysis; D007659:Ketones / Q000737:chemistry; D007783:Lactones / Q000737:chemistry; D008958:Models, Molecular; D012238:Rhodium / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D000475:Alkenes; D007659:Ketones; D007783:Lactones; D012238:Rhodium
keywords: CC activation; acylation; asymmetric catalysis; lactones; rhodium