ChemInform Abstract: Ligand‐Promoted Reactivity of Alkenes in Dehydrogenative Heck Reactions of Furans and Thiophenes.

Abstract

Ligand-Promoted Reactivity of Alkenes in Dehydrogenative Heck Reactions of Furans and Thiophenes. -4,5-Diazafluorenone is found to be an effective ligand for the dehydrogenative Heck reaction of cinnamic acid derivatives or stilbenes with thiophenes and furanes. According to kinetic and competitive experiments, the ligand has an influence on all steps of the catalytic cycle. -(VASSEUR, A.; LAUGEL, C.; HARAKAT, D.; MUZART, J.; LE BRAS*, J.; Eur. J. Org. Chem. 2015, 5, 944-948, http://dx.doi.org/10.1002/ejoc.201403475 ; Unite Mixte Rech., CNRS, Univ. Reims-Champagne-Ardenne, F-51687 Reims, Fr.; Eng.) -H. Haber 25-080

Operando Spectroscopic and Kinetic Characterization of Aerobic Allylic C–H Acetoxylation Catalyzed by Pd(OAc)2/4,5-Diazafluoren-9-one

“…31,58 The implications of these observations were not extended to catalytic conditions, however, and the present study provides a comprehensive analysis of the catalytic mechanism, including kinetic studies and operando X-ray absorption spectroscopy (XAS) and NMR spectroscopic analysis of the catalytic reaction, which reveal changes in the identity of the turnover limiting step and evolution of the catalyst species during the reaction. The results provide valuable insights into Pdcatalyzed allylic oxidation reactions and the ability of DAF to support aerobic catalytic turnover, [59][60][61][62][63][64][65][66][67][68][69] and this study establishes an important foundation for future empirical and mechanistic efforts directed toward the identification of more efficient and synthetically useful allylic C-H oxidation catalyst systems.…”