52279-00-2Relevant articles and documents
Catalytic Carbonyl-Olefin Metathesis of Aliphatic Ketones: Iron(III) Homo-Dimers as Lewis Acidic Superelectrophiles
Albright, Haley,Riehl, Paul S.,McAtee, Christopher C.,Reid, Jolene P.,Ludwig, Jacob R.,Karp, Lindsey A.,Zimmerman, Paul M.,Sigman, Matthew S.,Schindler, Corinna S.
supporting information, p. 1690 - 1700 (2019/01/26)
Catalytic carbonyl-olefin metathesis reactions have recently been developed as a powerful tool for carbon-carbon bond formation. However, currently available synthetic protocols rely exclusively on aryl ketone substrates while the corresponding aliphatic analogs remain elusive. We herein report the development of Lewis acid-catalyzed carbonyl-olefin ring-closing metathesis reactions for aliphatic ketones. Mechanistic investigations are consistent with a distinct mode of activation relying on the in situ formation of a homobimetallic singly bridged iron(III)-dimer as the postulated active catalytic species. These "superelectrophiles" function as more powerful Lewis acid catalysts that form upon association of individual iron(III)-monomers. While this mode of Lewis acid activation has previously been postulated to exist, it has not yet been applied in a catalytic setting. The insights presented are expected to enable further advancement in Lewis acid catalysis by building upon the activation principle of "superelectrophiles" and to broaden the current scope of catalytic carbonyl-olefin metathesis reactions.
Efficient and selective Al-catalyzed alcohol oxidation via oppenauer chemistry
Graves, Christopher R.,Zeng, Bi-Shun,Nguyen, SonBinh T.
, p. 12596 - 12597 (2008/02/03)
A highly active and selective Al-based catalytic Oppenauer (O) oxidation is reported. Quantitative and selective oxidations of a variety of benzylic, propargylic, allylic, and aliphatic primary and secondary alcohols were achieved using nitrobenzaldehyde derivatives as the oxidant and simple aluminum compounds as precatalysts. Copyright
Photochemistry of α,α,ω,ω-tetramethyl-1,2-cycloalkanediones; influence of the conformation of the diketo moiety on the photochemical behaviour
Verheijdt, Paul L.,Cerfontain, Hans
, p. 173 - 181 (2007/10/02)
A series of α,α,ω,ω-tetramethyl-1,2-cycloalkanediones, with a ring size varying between 4 and 8 C atoms (1a-e), together with 2,2,5,5-tetramethyl-3,4-hexanedione (2a), have been irradiated both in 2-propanol and in benzene in order to study the influence of the diketo conformation on the photochemical behaviour of 1,2-diketones.Irradiation of 1b-d in 2-propanol leads exclusively to photoreduction with formation of the corresponding acyloins via intermolecular H abstraction, whereas 1e and 2 yield predominantly the 2-hydroxycyclobutanone product via intramolecular H abs traction.The irradiations of 1a-e in benzene lead to different products for the six homologous cyclic 1,2-diketones.Mechanisms for the formation of the various products are proposed.It is concluded that the 1,2-diketones with Φ (ground state) 90 deg react, upon excitation, from a conformation having a planar cisoid and transoid diketo geometry, respectively.
