| Autor: |
Angel Palillero-Cisneros, Paola G. Gordillo-Guerra, Fernando García-Alvarez, Olivier Jackowski, Franck Ferreira, Fabrice Chemla, Joel L. Terán, Alejandro Perez-Luna |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Beilstein Journal of Organic Chemistry, Vol 19, Iss 1, Pp 1443-1451 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
1860-5397 |
| DOI: |
10.3762/bjoc.19.103 |
| Popis: |
We demonstrate that α-(aminomethyl)acrylates are suitable acceptors for 1,4-additions of dialkylzincs in aerobic conditions. The air-promoted radical–polar crossover process involves the 1,4-addition of an alkyl radical followed by homolytic substitution at the zinc atom of dialkylzinc. Coordination of the nitrogen atom to zinc enables this SH2 process which represents a rare example of alkylzinc-group transfer to a tertiary α-carbonyl radical. The zinc enolate thus formed readily undergoes β-fragmentation unless it is trapped by electrophiles in situ. Enolates of substrates having free N–H bonds undergo protodemetalation to provide ultimately the 1,4-addition adduct. In the presence of carbonyl acceptors, aldol condensation occurs providing overall a tandem 1,4-addition–aldol process. When a tert-butanesulfinyl moiety is present on the nitrogen atom, these electrophilic substitution reactions occur with good levels of chiral induction, paving the way to enantioenriched β2-amino acids and β2,2-amino acids. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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