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Abstract A protocol for the iterative decarboxylative cross‐coupling of carboxylic acids with dehydroalanine (Dha) allyl esters is described. A procedure for decarboxylative Giese addition to dehydroalanine allyl esters that avoids 5‐exo‐trig radical cyclization onto the allyl moiety was developed. This results in complex, substituted alanine allyl esters that are poised for a second decarboxylative coupling. Thus, following the photocatalytic decarboxylative alkylation of Dha, the resulting amino acid allyl esters were subjected to decarboxylative allylation under metallaphotoredox/palladium catalysis. The Giese addition and decarboxylative allylation can be performed in one pot simply by triggering the decarboxylative allylation by addition of a palladium catalyst. These one‐pot decarboxylative couplings leverage temporally controlled carboxylate formation to allow controlled, sequential photoredox activation of the carboxylates. The ability to perform sequential, one‐pot photoredox C─C bond formations obviates the need for isolation of intermediates. The final products of these coupling reactions are densely functionalized homoallylic amines and/or unsymmetric, differentiated 1,3‐diamines, both known for their high synthetic value.
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The Evolution of Decarboxylative Allylation: Overcoming p K a Limitations
Abstract Since early focus on development of the allylation of non‐stabilized enolates, decarboxylative allylation has undergone tremendous evolution. This account describes the progression of decarboxylative allylation within the Tunge group with a focus on efforts to identify and overcome pKarequirements that initially limited the carboxylates that would undergo decarboxylative allylation.
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- Award ID(s):
- 1800147
- PAR ID:
- 10135825
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Israel Journal of Chemistry
- Volume:
- 60
- Issue:
- 3-4
- ISSN:
- 0021-2148
- Page Range / eLocation ID:
- p. 351-359
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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