69060-18-0Relevant articles and documents
Nickel-Catalyzed Asymmetric Reductive 1,2-Carboamination of Unactivated Alkenes
He, Jun,Xue, Yuhang,Han, Bo,Zhang, Chunzhu,Wang, You,Zhu, Shaolin
supporting information, p. 2328 - 2332 (2020/01/08)
Starting from diverse alkene-tethered aryl iodides and O-benzoyl-hydroxylamines, the enantioselective reductive cross-electrophilic 1,2-carboamination of unactivated alkenes was achieved using a chiral pyrox/nickel complex as the catalyst. This mild, modular, and practical protocol provides rapid access to a variety of β-chiral amines with an enantioenriched aryl-substituted quaternary carbon center in good yields and with excellent enantioselectivities. This process reveals a complementary regioselectivity when compared to Pd and Cu catalysis.
Pd-Catalyzed Carbonylation of Vinyl Triflates to Afford α,β-Unsaturated Aldehydes, Esters, and Amides under Mild Conditions
Zhang, Shaoke,Neumann, Helfried,Beller, Matthias
, p. 3528 - 3532 (2019/05/24)
An efficient and general protocol for the synthesis of α,β-unsaturated aldehydes, esters, and amides via carbonylation of vinyl triflates including derivatives of camphor, ketoisophorone, verbenone, and pulegone was developed. Crucial for these transformations is the use of a specific palladium catalyst containing a pyridyl-substituted dtbpx-type ligand. This procedure also allows for an easy access of dicarbonylated products from the corresponding ketones.
Catalytic, enantioselective, and highly chemoselective bromocyclization of olefinic dicarbonyl compounds
Zhao, Yi,Jiang, Xiaojian,Yeung, Ying-Yeung
supporting information, p. 8597 - 8601 (2013/09/12)
Overriding preferences: An amine-thiocarbamate catalyst can mediate the facile, efficient, and highly enantioselective bromocyclization of olefinic 1,3-dicarbonyl compounds. In the presence of the bifunctional catalyst, the bromination occurs chemoselectively at the olefinic moiety rather than at the carbon atom in the α-position to the carbonyl units. Copyright
Manganese(III) acetate mediated oxidative radical cyclizations. Toward vicinal all-carbon quaternary stereocenters
Logan, Angus W.J.,Parker, Jeremy S.,Hallside, Michal S.,Burton, Jonathan W.
, p. 2940 - 2943 (2012/08/28)
Manganese(III) acetate mediated oxidative radical cyclizations have been used to synthesize a range of densely functionalized and sterically congested cyclopentane-lactones. A number of the resulting lactones contain vicinal all-carbon quaternary stereocenters adjacent to a tertiary benzylic stereocenter and are formed with high levels of stereocontrol.
SPIROINDOLINONE DERIVATIVES
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Page/Page column 70, (2008/06/13)
The present invention relates to spiroindolinone derivatives of the formula and their enantiomers and pharmaceutically acceptable salts and esters thereof wherein R1, R2, R3, R4, R5, R6, R7 and R8, are as herein described.
Rapid organocatalytic aldehyde-aldehyde condensation reactions
Erkkilae, Anniina,Pihko, Petri M.
, p. 4205 - 4216 (2008/03/14)
We report the results of the systematic optimization of the α-methylenation of aldehydes with aqueous formaldehyde. A simple combination of a secondary amine catalyst and a weak acid co-catalyst has been identified, allowing access to α-substituted acroleins in a matter of minutes. In the absence of formaldehyde, the catalytic system promoted the self-condensation reaction of α,β-unsaturated aldehydes. Both of these reactions exhibited linear relationships between co-catalyst acidities and reaction rates. A second-order dependence of catalyst concentration was observed, pointing to the involvement of two molecules of the ammonium catalyst in the rate-determining step. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Simple primary anilines as iminium catalysts for the epoxidation of α-substituted acroleins
Erkkilae, Anniina,Pihko, Petri M.,Clarke, Melanie-Rose
, p. 802 - 806 (2008/03/18)
Simple ortho-alkylated anilines have been shown to be excellent iminium catalysts for the epoxidation reaction of α-substituted acroleins. A range of different α-substituted acroleins give the epoxide products in good to excellent yields and good chemoselectivity.
Mild organocatalytic α-methylenation of aldehydes
Erkkil?, Anniina,Pihko, Petri M.
, p. 2538 - 2541 (2007/10/03)
A rapid and extremely convenient method for α-methylenation of aldehydes with aqueous formaldehyde is described. Two optimal catalytic systems are presented that allow short reaction times and afford the functionalized products in good to excellent yields (up to 99%) and chemoselectivity.
Diastereoselective hydroformylation of 2-substituted allylic o-DPPB-Esters-On the origin of 1,2-asymmetric induction
Breit, Bernhard,Heckmann, Golo,Zahn, Stephan K.
, p. 425 - 434 (2007/10/03)
2-Substituted secondary alcohol o-DPPB esters (o-DPPB = orthodiphenylphosphanylbenzoyl) have been prepared and their o-DPPB-directed diastereoselective hydroformylation examined. It was found that the diastereoselectivity increased as a function of the steric demand of the substituents both at the stereogenic center and in the alkene 2-position. Hydrolytic cleavage of the o-DPPB group afforded - via the lactols 29 - the corresponding lactones 30, the relative configurations of the vicinal stereogenic centers of which were ascertainable by 2D-NOESY spectroscopy. In addition, a crystal structure analysis of the hydroformylation product 2d provided further confirmation of the relative configuration. Replacement of the ester carbonyl group of the o-DPPB by a methylene unit resulted in significantly worse diastereoselectivity in the course of the hydroformylation (34→35), which indicates a decisive role for the ester carbonyl function. All the experimental observations were combined in a model of the origin of the 1,2-asymmetric induction during the title reaction. The key feature is the consideration of diastereomeric trigonal-bipyramidal rhodium-hydrido-olefin complexes I and II, capable on the basis of the Hammond postulate of acting as good models for the transition states of the selectivity-determining hydrometalation step. Investigation of these complexes by force-field methods indicated good correlation between theoretically predicted and experimentally determined diastereoselectivities.
