936632-17-6Relevant academic research and scientific papers
C?N Axial Chiral Hypervalent Iodine Reagents: Catalytic Stereoselective α-Oxytosylation of Ketones
Alharbi, Haifa,Elsherbini, Mohamed,Qurban, Jihan,Wirth, Thomas
supporting information, p. 4317 - 4321 (2021/02/16)
A simple synthesis of a library of novel C?N axially chiral iodoarenes is achieved in a three-step synthesis from commercially available aniline derivatives. C?N axial chiral iodine reagents are rarely investigated in the hypervalent iodine arena. The potential of the novel chiral iodoarenes as organocatalysts for stereoselective oxidative transformations is assessed using the well explored, but challenging stereoselective α-oxytosylation of ketones. All investigated reagents catalyse the stereoselective oxidation of propiophenone to the corresponding chiral α-oxytosylated products with good stereochemical control. Using the optimised reaction conditions a wide range of products was obtained in generally good to excellent yields and with good enantioselectivities.
Asymmetric α-Sulfonyl- and α-Phosphoryl-Oxylation of Ketones by a Chiral Hypervalent Iodine(III)
Levitre, Guillaume,Dumoulin, Audrey,Retailleau, Pascal,Panossian, Armen,Leroux, Frédéric R.,Masson, Géraldine
, p. 11877 - 11883 (2017/11/24)
An enantioselective direct oxygenation of propiophenone derivatives mediated by a catalytic or stoichiometric amount of new chiral non-C2-symmetric iodoarenes(III) is reported. The reaction gives an easy entry to optically active α-sulfonyl- and α-phosphoryl oxyketones in respectable yields and enantioselectivities.
Enantioselective Iodine(III)-Mediated Synthesis of α-Tosyloxy Ketones: Breaking the Selectivity Barrier
Basdevant, Benoit,Legault, Claude Y.
, p. 4918 - 4921 (2015/10/12)
The development of practical methods to access chiral nonracemic α-substituted ketones is of particular importance due to their ubiquitous nature. Unprecedented levels of enantioselectivity are reported for the synthesis of α-tosyloxy ketones, using enol esters and chiral iodine(III) reagents. The reaction can be performed under both stoichiometric and catalytic conditions. These results suggest widely different reaction mechanisms for the reaction of ketones versus enol esters, supporting recent computational insights.
Catalytic enantioselective α-tosyloxylation of ketones using iodoaryloxazoline catalysts: Insights on the stereoinduction process
Guilbault, Audrey-Anne,Basdevant, Benoit,Wanie, Vincent,Legault, Claude Y.
, p. 11283 - 11295 (2013/02/23)
A family of iodooxazoline catalysts was developed to promote the iodine(III)-mediated α-tosyloxylation of ketone derivatives. The α-tosyloxy ketones produced are polyvalent chiral synthons. Through this study, we have unearthed a unique mode of stereoinduction from the chiral oxazoline moiety, where the stereogenic center alpha to the oxazoline oxygen atom is significant. Computational chemistry was used to rationalize the stereoinduction process. The catalysts presented promote currently among the best levels of activity and selectivity for this transformation. Evaluation of the scope of the reaction is presented.
Enantioselective α-tosyloxylation of ketones catalyzed by spirobiindane scaffold-based chiral iodoarenes
Yu, Jun,Cui, Jian,Hou, Xue-Sen,Liu, Shan-Shan,Gao, Wen-Chao,Jiang, Shan,Tian, Jun,Zhang, Chi
scheme or table, p. 2039 - 2055 (2012/03/11)
Enantiomerically pure iodoarene (S)-2 and its derivatives (S)-3 to (S)-18 with a spirobiindane scaffold have been synthesized. The evaluation of these new chiral iodoarenes as catalysts in the enantioselective α-tosyloxylation of ketones was performed using m-CPBA as a stoichiometric oxidant, and the synthetically useful α-tosyloxylated ketones were obtained in up to 58% enantiomeric excess (ee).
Catalytic enantioselective α-oxysulfonylation of ketones mediated by iodoarenes
Altermann, Sabine M.,Richardson, Robert D.,Page, T. Keri,Schmidt, Ruth K.,Holland, Edward,Mohammed, Umal,Paradine, Shauna M.,French, Andrew N.,Richter, Christine,Bahar, A. Masih,Witulski, Bernhard,Wirth, Thomas
experimental part, p. 5315 - 5328 (2009/07/11)
The α-oxysulfonylation of ketones catalysed by enantio enriched iodoarenes using mCPBA as stoichiometric oxidant is reported to give useful synthetic intermediates in good yield and modest enantioselectivity. We believe this to be the first report of an enantioselective organocatalytic reaction involving hypervalent iodine reagents which should open up a new field for enantioselective organocatalysis of oxidation reactions. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
