Abstract
A nickel-catalyzed β-selective hydrocarboxylation of ynamides to give protected dehydro-β-amino acids was developed. The key to exclusive β-selectivity was the use of diethylzinc as a reductant in the presence of a magnesium salt. The reaction was conducted with bis(acetylacetonato)nickel(II) instead of costly and sensitive bis(1,5-cyclooctadiene)nickel(0). In addition, the optimized ligand was inexpensive 1,5-cyclooctadiene. Investigation of the substrate scope revealed that both nitrogen and alkyne substituents have marked effects on the reaction efficiency. We obtained experimental clues that indicated the formation of a vinylzinc intermediate that forms a C-C bond with CO 2 .
Original language | English |
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Pages (from-to) | 1048-1052 |
Number of pages | 5 |
Journal | Synlett |
Volume | 30 |
Issue number | 9 |
DOIs | |
Publication status | Published - 1 Jan 2019 |
Keywords
- carbon dioxide
- hydrocarboxylation
- nickel catalysis
- ynamides
- β-amino acids