10.1021/ol800298n
The research focuses on the construction of highly functionalized diazoacetoacetates through catalytic Mukaiyama?Michael reactions. The study involves the reaction between methyl 3-(trialkylsilanoxy)-2-diazo-3-butenoate and α,β-unsaturated enones, utilizing zinc(II) triflate as the optimal catalyst with a remarkably low loading of 0.1 mol %. The experiments conducted aimed to develop an efficient methodology for synthesizing complex diazo compounds under mild conditions, overcoming previous challenges associated with harsh reaction conditions and the instability of diazo compounds in the presence of Lewis acids. The researchers employed a series of catalyst screenings and optimizations, ultimately achieving good to excellent yields of vinyl ether and ketone derivatives. The analyses included monitoring the reaction progress, isolating the products, and characterizing them using spectroscopic data, which were detailed in the supporting information. This research significantly advances the field by providing a mild, efficient, and practical approach to synthesize diazoacetoacetates, which are valuable intermediates in organic synthesis.
10.1021/acscatal.9b02512
The research presented in the "ACS Catalysis" article focuses on the Rh(III)-catalyzed regioselective C?H amidation of N-methoxy-1H-indole-1-carboxamides by 1,4,2-dioxazol-5-ones, exploring how the directing group (DG), specifically the N-methoxy amide, influences the reaction's outcome. The study experimentally and computationally investigates the chameleon-like behavior of the DG under various conditions, leading to four distinct transformation pathways: DG-retained, DG-coupled, DG-eliminated, and DG-migrated processes. The experiments involved using [Cp*RhCl2]2 and Zn(OTf)2 as catalysts, with NaOAc as a base and solvents like DCE and THF, alongside the addition of water and K2S2O8 under different temperatures to achieve selective transformations. The analyses included optimization of reaction conditions, substrate scope evaluation, and mechanistic studies through DFT calculations, which provided insights into the reaction mechanisms and the role of the N-methoxy amide DG in the regioselective C?H amidation process.