475644-71-4Relevant academic research and scientific papers
BIMP-Catalyzed 1,3-Prototropic Shift for the Highly Enantioselective Synthesis of Conjugated Cyclohexenones
Carter, Eve M.,Dixon, Darren J.,Golec, Jonathan C.,Paton, Robert S.,Simón, Luis,Ward, John W.,Whittingham, William G.
supporting information, p. 17417 - 17422 (2020/08/10)
A bifunctional iminophosphorane (BIMP)-catalysed enantioselective synthesis of α,β-unsaturated cyclohexenones through a facially selective 1,3-prototropic shift of β,γ-unsaturated prochiral isomers, under mild reaction conditions and in short reaction times, on a range of structurally diverse substrates, is reported. α,β-Unsaturated cyclohexenone products primed for downstream derivatisation were obtained in high yields (up to 99 %) and consistently high enantioselectivity (up to 99 % ee). Computational studies into the reaction mechanism and origins of enantioselectivity, including multivariate linear regression of TS energy, were carried out and the obtained data were found to be in good agreement with experimental findings.
Straightforward synthesis of nonconjugated cyclohex-3-enone and conjugated 4-methylenecyclohex-2-enone derivatives
Kuttner, Julian R.,Warratz, Svenja,Hilt, Gerhard
, p. 1293 - 1303 (2012/06/30)
The synthesis of nonconjugated cyclohex-3-enones via the regiodivergent cobalt-catalysed Diels-Alder reactions of 2-(trimethylsilyloxy)buta-1,3-diene with alkynes and hydrolysis of the dihydroaromatic intermediates is described. The application of bidentate phosphine ligands versus pyridine-imine ligands led to the regioselective formation of one out of the two possible regioisomeric products when terminal or unsymmetrically substituted alkynes were applied. The cyclohex-3-enone products were isolated mostly in good yields without isomerisation of the carbon-carbon double bond into conjugation based on the mild reaction conditions. The use of acetoxymethyl-substituted alkynes led to the conjugated 4-methylenecyclohex-2-enones after deprotection of the silyl enol ether. Georg Thieme Verlag Stuttgart · New York.
Cobalt(I)-catalyzed neutral Diels-Alder reactions of oxygen-functionalized acyclic 1,3-dienes with alkynes
Hilt, Gerhard,Smolko, Konstantin I.,Lotsch, Bettina V.
, p. 1081 - 1084 (2007/10/03)
The cobalt-catalyzed Diels-Alder reaction of alkoxy-substituted 1,3-butadienes with terminal and internal alkynes is described. While the reaction of 1-alkoxy derivatives gave the aromatic hydrocarbons upon elimination of alcohol from the alkoxy-substituted dihydroaromatic intermediates, the reactions with 2-alkoxy derivatives generated stable dihydroaromatic enol ethers in good to excellent chemical yields and good to high regioselectivities for unsymmetrical starting materials. The enol ethers can be easily hydrolysed to the corresponding β,γ-unsaturated ketones in a one pot reaction sequence or used in cyclopropanation or other subsequent chemical transformations.
