The γ-functionalization of oxindoles bearing nonsymmetric 3-alkylidene groups via vinylogous Michael-type addition to nitroolefins was realized. The suppression of the interconversion between the E and Z isomers of the starting oxindoles allowed a site-specific diastereoselective and enantioselective transformation. Specific experiments allowed us to establish the rate-determining step of the reaction and to advance a robust hypothesis for the exclusive formation of an s-cis enolate as the only reactive intermediate.
Vinylogous Reactivity of Oxindoles Bearing Nonsymmetric 3-Alkylidene Groups / Di Iorio, N.; Righi, P.; Ranieri, S.; Mazzanti, A.; Margutta, R.G.; Bencivenni, G.. - In: JOURNAL OF ORGANIC CHEMISTRY. - ISSN 0022-3263. - STAMPA. - 80:14(2015), pp. 7158-7171. [10.1021/acs.joc.5b01022]
Vinylogous Reactivity of Oxindoles Bearing Nonsymmetric 3-Alkylidene Groups
DI IORIO, NICOLA;RIGHI, PAOLO;RANIERI, SILVIA;MAZZANTI, ANDREA;BENCIVENNI, GIORGIO
2015
Abstract
The γ-functionalization of oxindoles bearing nonsymmetric 3-alkylidene groups via vinylogous Michael-type addition to nitroolefins was realized. The suppression of the interconversion between the E and Z isomers of the starting oxindoles allowed a site-specific diastereoselective and enantioselective transformation. Specific experiments allowed us to establish the rate-determining step of the reaction and to advance a robust hypothesis for the exclusive formation of an s-cis enolate as the only reactive intermediate.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.