Stereoselektive Additionsreaktionen mit Nitrosoderivaten
Zusammenfassung der Projektergebnisse
The project was dealing with the use of nitroso arenes as electrophiles in various stereo-selective transformations. Initial studies focused on Cu-catalyzed processes. It was found that 2-nitroso-pyridine in combination with a chiral Cu-catalyst reacts with high enantio and region-selectivity in various cycloaddition reactions. For example, the nitroso Diels Alder reaction was achieved using this approach with high selectivity and also (2+2) cycloadditions with ketenes as reaction partners were found to occur with high stereo-control. We also found that allylstannanes react with high stereoselectivity with nitroso arenes under Cu-catalysis. Transition-metal free reactions were also explored. Along these lines, Lewis acid catalyzed allylations of nitroso arenes with allylboronic esters were investigated and it was found that chiral allyl boronates react with excellent stereo-specificity to valuable compounds. In situ generated arynes were found to react with nitroso arenes to carbazoles. Moreover, we noted that donor-acceptor cyclopropanes engage as formal 1,3-dipoles in transformations with nitroso arenes to give isoxazolidines. Importantly, starting with readily accessible enantiomerically pure donor-acceptor cyclopropanes, these product isoxazolidines are formed with complete enantio-specificity. Follow-up chemistry further documented the potential of this novel method. Finally, we found that with donor-acceptor cyclopropanes as substrates and nitroso arenes as reaction partners, tetrahydroquinolines are accessible.
Projektbezogene Publikationen (Auswahl)
- Copper Catalyzed Enantioselective [2+2] Cycloadditions of 2-Nitrosopyridine with Ketenes. Advanced Synthesis & Catalysis, Vol. 352. 2010, Issue 6, pp. 945–948.
I. Chatterjee, C. Kumar Jana, M. Steinmetz, S. Grimme, A. Studer
(Siehe online unter https://dx.doi.org/10.1002/adsc.201000153) - Formation of Isoxazolidines by Enantioselective Copper-Catalyzed Annulation of 2-Nitrosopyridine with Allylstannanes. Angewandte Chemie International Edition, Vol. 50. 2011, Issue 47, pp. 11257–11260.
I. Chatterjee, R. Fröhlich, A. Studer
(Siehe online unter https://dx.doi.org/10.1002/anie.201105515) - Reactions of Arynes with Nitrosoarenes-An Approach to Substituted Carbazoles. Angewandte Chemie International Edition, Vol. 52. 2013, Issue 10, pp. 2968–2971.
S. Chakrabarty, I. Chatterjee, L. Tebben, A. Studer
(Siehe online unter https://doi.org/10.1002/anie.201209447) - Stereospecific Formal [3+2] Dipolar Cycloaddition of Cyclopropanes with Nitrosoarenes - An Approach to Isoxazolidines, Angew. Chem. Int. Ed. 2014, 53, 5964–5968
S. Chakrabarty, I. Chatterjee, B. Wibbeling, C. G. Daniliuc, A. Studer
(Siehe online unter https://doi.org/10.1002/anie.201400885) - An Efficient Approach to Chiral Allyloxyamines by Stereospecific Allylation of Nitrosoarenes with Chiral Allylboronates. Angewandte Chemie International Edition, Vol. 54. 2015, Issue 12, pp. 3587–3591.
Y. Li, S. Chakrabarty, A. Studer
(Siehe online unter https://doi.org/10.1002/anie.201410188) - Multicomponent 1,3-Bifunctionalization of Donor-Acceptor Cyclopropanes with Arenes and Nitrosoarenes. Organic Letters, Vol. 18. 2016, Issue 21, pp. 5576–5579.
S. Das, C. G. Daniliuc, A. Studer
(Siehe online unter https://doi.org/10.1021/acs.orglett.6b02815) - Tetrahydroquinolines via Stereospecific [3+3]-Annulation of Donor−Acceptor Cyclopropanes with Nitrosoarenes. Organic Letters, Vol. 18. 2016, Issue 11, pp. 2784–2787.
S. Das, S. Chakrabarty, C. G. Daniliuc, A. Studer
(Siehe online unter https://doi.org/10.1021/acs.orglett.6b01302)
