Computational Study on the Synergic Effect of Brønsted Acid and Hydrogen-Bonding Catalysis for the Dearomatization Reaction of Phenols with Diazo Functionality

Development of Transition-Metal-Catalyzed Dearomatization Reactions

“…Our works on transition-metal-catalyzed dearomatization reactions is reviewed from the first report in 2010 on the Pd-catalyzed intramolecular ipso-Friedel-Crafts-type allylic alkylation of phenols to the development of Ag-catalyzed asymmetric ring expansion reactions reported in 2021. In addition to the studies presented in this review, organocatalytic dearomatization reactions using Brønsted acid/thiourea catalyst [40][41][42] and borane catalyst systems 43) have been successfully developed by our group (see cited references). Dearomatization has become one of the most attractive and competitive research topics in synthetic organic chemistry.…”

Development of Novel Methodology Using Diazo Compounds and Metal Catalysts

“…[14][15][16][17] Our group envisioned that chemoselective arene dearomatizations could be designed by applying an electrophilic metal-carbene if the competing C-H insertion and Buchner ring expansion could be suppressed by suitable selection of the metal-center and supporting ligands. Firstly, diazoamide 5a having 1°, 2° and 3° C-H bond near the reaction site was prepared to assess chemoselectivity [18][19][20] (Table 2). The reaction employing a rhodium or copper complex provided a mixture of C-H insertion products 8a and 9a, and tropone variant 7a through a Buchner reaction (entries 1 and 2).…”