Formation of unsaturated esters in the single electron transfer reaction of cyclopropanone acetals with quinones under non-irradiated conditions
作者:Manabu Abe、Akira Oku
DOI:10.1016/s0040-4039(00)73235-7
日期:1994.5
Unsaturated esters were formed from cyclopropanone acetals in the reaction with DDQ or chloranil, where ring-opened CC and CO bonded adducts were the intermediates formed via a SET mechanism resulting in the ester formation.
Electron Transfer Profile of Cyclopropanone Acetals in the Nonirradiated Reaction with Tetracyanoethylene, Chloranil, and Dicyanodichlorobenzoquinone
作者:Akira Oku、Manabu Abe、Masaharu Iwamoto
DOI:10.1021/jo00103a043
日期:1994.12
The donor profiles of cyclopropanone acetals 1 and 2 were examined in the reactions with electron accepters (TCNE, DDQ, chloranil, and 1-cyanonaphthalene). With TCNE under nonirradiating conditions, an exclusive 2 + 2 cycloaddition took place stereospecifically with monosubstituted acetals 1a-c but nonstereospecifically with disubstituted acetals 1d,e. With quinones, a ring-opening of the cyclopropane and its coupling with the quinone took place to give the C (cyclopropane)-O (quinone) adduct 9 (with chloranil) or 10 (with DDQ), the latter of which underwent the elimination of a phenol to produce unsaturated esters 5 and 6. In addition, the intervention of the C (cyclopropane)-C (quinone) adduct 14 (with chloranil) or 15 (with DDQ), both as the precursor of 5 and 6, was also postulated. With 1-cyanonaphthalene, under photolysis, the cis/trans isomerization of 1 and 2 occurred. The results provided evidences that cyclopropanone acetals, in general, are prone to function as donors. The mechanism of the reaction with quinones, in particular, was investigated in detail.
Abe Manabu, Oku Akira, Tetrahedron Lett, 35 (1994) N 21, S 3551-3554
作者:Abe Manabu, Oku Akira
DOI:——
日期:——
Photochemistry of β, γ-unsaturated ketones-V
作者:Anton J.A. Van der Weerdt、Hans Cerfontain
DOI:10.1016/s0040-4020(01)97968-2
日期:1981.1
The photochemistry of some members of the two series of γ-phenyl substituted acyclic β, γ-unsaturatedketones 1 and 2 upon direct irradiation with γ 310nm has been investigated, viz 1c–1h and 2b+2c.The alkyl substituted (E)-5-phenyl-4-penten-2-ones 1c–1h yield the corresponding 1,3-acyl shift products and (Z)-isomers, and 1g and 1h in addition two decarbonylated products. 2b only yields the (Z)-isomer
Tetrasubstituted Olefins through the Stereoselective Catalytic Intermolecular Conjugate Addition of Simple Alkenes to α,β-Unsaturated Carbonyl Compounds
作者:Ki-Hyeok Kwon、Do W. Lee、Chae S. Yi
DOI:10.1002/anie.201006411
日期:2011.2.11
Branching out: The cationic ruthenium–hydride complex [Ru]+ was found to be a highly effective catalyst precursor for the conjugate addition of unactivated olefins to α,β‐unsaturated carbonylcompounds to yield tetrasubstituted olefins. A kinetic analysis provides support for the mechanism involving a regioselective olefin insertion and rapid alkene isomerization steps.