| 1. |
- Bergonzini, Giulia, 1985, et al.
(författare)
-
Acyl Radicals from Aromatic Carboxylic Acids by Means of Visible-Light Photoredox Catalysis.
- 2015
-
Ingår i: Angewandte Chemie (International ed. in English). - : Wiley. - 1521-3773. ; 54:47, s. 14066-14069
-
Tidskriftsartikel (refereegranskat)abstract
- Simple and abundant carboxylic acids have been used as acyl radical precursor by means of visible-light photoredox catalysis. By the transient generation of a reactive anhydride intermediate, this redox-neutral approach offers a mild and rapid entry to high-value heterocyclic compounds without the need of UV irradiation, high temperature, high CO pressure, tin reagents, or peroxides.
|
|
| 2. |
- Bergonzini, Giulia, 1985, et al.
(författare)
-
Visible-Light-Mediated Photocatalytic Difunctionalization of Olefins by Radical Acylarylation and Tandem Acylation/Semipinacol Rearrangement
- 2016
-
Ingår i: Chemistry-a European Journal. - : Wiley. - 0947-6539. ; 22:10, s. 3292-3295
-
Tidskriftsartikel (refereegranskat)abstract
- A novel method for the mild photoredox-mediated tandem radical acylarylation and tandem acylation/semipinacol rearrangement has been developed. The synthesis of highly functionalized ketones bearing all-carbon - or -quaternary centers has been achieved using easily available symmetric aromatic carboxylic anhydrides as the acyl radical source. The method allows for a straightforward introduction of the keto functionality and concomitant construction of molecular complexity in a single operation.
|
|
| 3. |
- Cassani, Carlo, 1984, et al.
(författare)
-
Active Species and Mechanistic Pathways in Iron-Catalyzed C-C Bond-Forming Cross-Coupling Reactions
- 2016
-
Ingår i: Acs Catalysis. - : American Chemical Society (ACS). - 2155-5435. ; 6:3, s. 1640-1648
-
Tidskriftsartikel (refereegranskat)abstract
- Over the past decade, considerable progress on iron-catalyzed C-C bond-forming cross-coupling reactions has been made, leading to the successful development of several new catalytic systems. This perspective presents the proposed mechanistic pathways of iron-mediated cross-coupling reactions of organohalides and Grignard reagents and discusses the evidence documented in the literature that distinguishes whether such pathways proceed via single- or double-electron processes. When cross-coupling reactions are conducted in the presence of ligands, there is still much discussion in the literature as to whether the lowest iron oxidation state responsible for catalytic activity is Fe(I) or Fe(II). However, when ligand-free conditions are employed, it has been shown that iron reaches an Fe(I) oxidation state, allowing an Fe(I)/Fe(III) catalytic cycle. Moreover, for cross-couplings using alkyl halide electrophiles, evidence suggests that the reaction proceeds through single-electron steps, with the generation of an alkyl radical. While this topic is still the subject of much debate, it is thought that reactions of alkyl Grignards with aryl and alkenyl electrophiles proceed via a double-electron pathway.
|
|
| 4. |
- Cassani, Carlo, 1984, et al.
(författare)
-
Photocatalytic decarboxylative reduction of carboxylic acids and its application in asymmetric synthesis
- 2014
-
Ingår i: Organic Letters. - : American Chemical Society. - 1523-7060 .- 1523-7052. ; 16:16, s. 4228-4231
-
Tidskriftsartikel (refereegranskat)abstract
- The decarboxylative reduction of naturally abundant carboxylic acids such as α-amino acids and α-hydroxy acids has been achieved via visible-light photoredox catalysis. By using an organocatalytic photoredox system, this method offers a mild and rapid entry to a variety of high-value compounds including medicinally relevant scaffolds. Regioselective decarboxylation is achieved when differently substituted dicarboxylic acids are employed. The application of this method to the synthesis of enantioenriched 1-aryl-2,2,2-trifluoroethyl chiral amines starting from natural α-amino acids further testifies to the utility of the developed photocatalytic decarboxylative reduction protocol.
|
|
