Aminofluorination of 2-alkynylanilines: a Au-catalyzed entry to fluorinated indoles

• Antonio Arcadi,
• Emanuela Pietropaolo,
• Antonello Alvino and
• Véronique Michelet

Beilstein J. Org. Chem. 2014, 10, 449–458, doi:10.3762/bjoc.10.42

• fluorination strategies by using Selectfluor as an electrophilic source of fluorine [24][25][26][27][28][29][30][31] can provide a powerful tool for building up nitrogen heterocycle derivatives. Fluorinated pyrrolidines [32] and fluorinated pyrazoles [33] have been synthesized from 1,ω-N-protected aminoalkynes

Stereoselectively fluorinated N-heterocycles: a brief survey

• Xiang-Guo Hu and
• Luke Hunter

Beilstein J. Org. Chem. 2013, 9, 2696–2708, doi:10.3762/bjoc.9.306

• the entire pyrrolidine ring by 180° relative to that of 9, and several different H-bonding contacts with the DNA as a result. In contrast with the strong charge–dipole effect evident in pyrrolidine 10 (Figure 3), another more subtle interaction is observed in neutral fluorinated pyrrolidines. For

Combination of gold catalysis and Selectfluor for the synthesis of fluorinated nitrogen heterocycles

• Antoine Simonneau,
• Pierre Garcia,
• Jean-Philippe Goddard,
• Virginie Mouriès-Mansuy,
• Max Malacria and
• Louis Fensterbank

Beilstein J. Org. Chem. 2011, 7, 1379–1386, doi:10.3762/bjoc.7.162

• the elucidation of the mechanism and Selectfluor was suggested to play the double role of promoting the oxidation of gold(I) to a gold(III) active species and also the electrophilic fluorination of the enamine intermediates. Keywords: cycloisomerization reactions; fluorinated pyrrolidines; gold

• fluorinated pyrrolidines 3a, 4a and 2-pyrroline 5a are unknown and could be interesting building blocks for organic synthesis. Following the previous catalyst screening, we stuck with the use of PPh3AuCl as the catalyst and next investigated the effect of the concentration of 1a and the stoichiometry of

• isolated in 43% yield (Scheme 3). Our mechanistic proposal for the formation of fluorinated pyrrolidines is outlined in Scheme 4. Oxidation of the Au(I) complex by Selectfluor should give the active cationic Au(III) species A. Formation of A is consistent with 19F NMR experiments analogous to those