866395-16-6Relevant articles and documents
Synthesis of Polysubstituted Fused Pyrroles by Gold-Catalyzed Cycloisomerization/1,2-Sulfonyl Migration of Yndiamides
Smith, Philip J.,Jiang, Yubo,Tong, Zixuan,Pickford, Helena D.,Christensen, Kirsten E.,Nugent, Jeremy,Anderson, Edward A.
supporting information, p. 6547 - 6552 (2021/08/30)
Yndiamides (bis-N-substituted alkynes) are valuable precursors to azacycles. Here we report a cycloisomerization/1,2-sulfonyl migration of alkynyl-yndiamides to form tetrahydropyrrolopyrroles, unprecedented heterocyclic scaffolds that are relevant to medicinal chemistry. This functional group tolerant transformation can be achieved using Au(I) catalysis that proceeds at ambient temperature, and a thermally promoted process. The utility of the products is demonstrated by a range of reactions to functionalize the fused pyrrole core.
Synthesis and Structure Revision of Dichrocephones A and B
Schmiedel, Volker M.,Hong, Young J.,Lentz, Dieter,Tantillo, Dean J.,Christmann, Mathias
supporting information, p. 2419 - 2422 (2018/01/27)
Herein, we report the first enantioselective synthesis of dichrocephones A and B, which are cytotoxic triquinane sesquiterpenes with a dense array of stereogenic centers within a strained polycyclic environment. Key features include the application of a catalytic asymmetric Wittig reaction, followed by stereoselective functionalization of the propellane core into a pentacyclic intermediate. Double reductive ring cleavage yielded the proposed structure of dichrocephone A. Mismatched spectroscopic data for our synthetic material compared to the natural isolate led us to revise the previously proposed configuration based on biosynthetic considerations and NMR calculations. Implementation of these findings culminated in the synthesis of dichrocephones A and B.
Why can a gold salt react as a base?
Anania, Mariarosa,Ja?íková, Lucie,Ja?ík, Juraj,Roithová, Jana
supporting information, p. 7841 - 7852 (2017/10/06)
This study shows that gold salts [(L)AuX] (L = PMe3, PPh3, JohnPhos, IPr; X = SbF6, PF6, BF4, TfO, Tf2N) act as bases in aqueous solutions and can transform acetone to digold acetonyl complexes [(L)2Au2(CH2COCH3)]+ without any additional base present in solution. The key step is the formation of digold hydroxide complexes [(L)2Au2(OH)]+. The kinetics of the formation of the digold complexes and their mutual transformation is studied by electrospray ionization mass spectrometry and the delayed reactant labelling method. We show that the formation of digold hydroxide is the essential first step towards the formation of the digold acetonyl complex, the reaction is favoured by more polar solvents, and the effect of counter ions is negligible. DFT calculations suggest that digold hydroxide and digold acetonyl complexes can exist in solution only due to the stabilization by the interaction with two gold atoms. The reaction between the digold hydroxide and acetone proceeds towards the dimer {[(L)Au(OH)]·[(L)Au(CH3COCH3)]+}. The monomeric units interact at the gold atoms in the perpendicular arrangement typical of the gold clusters bound by the aurophilic interaction. The hydrogen is transferred within the dimer and the reaction continues towards the digold acetonyl complex and water.
