Dearomative C-C bond formation of benzyl phosphates has been developed. In the presence of a palladium/PAr catalyst, benzyl phosphates reacted with allyl borates to generate the allylated product in a dearomative fashion. The resulting dearomatized molecules were successfully derivatized by Simmons-Smith cyclopropanation and oxidation.

A catalytic dearomative three-component reaction of bromoarenes with TMS-diazomethane and allyl borate was developed. The key of this assembling reaction is the use of a diazo compound to generate a Pd-π-benzyl intermediate through a Pd-carbene species. This method allowed for a dearomative functionalization, using arenes as limiting reagents. Heteroaryl bromides were also applicable to give dearomatized structures under the reaction conditions.

A dearomative allylation of naphthyl cyanohydrins with allyl borates and allyl stannanes under palladium catalysis was developed. At the initial stage of this study, the dearomative reaction (C4 substitution of the aromatics) was competing with benzyl substitution. To circumvent this issue, the use of palladium and meta-disubstituted triarylphosphine as the catalyst in a 1:1 ratio was found to enhance the site selectivity, furnishing the desired dearomatized products. Further derivatizations of products were also successful.

A Pd-catalyzed dearomative three-component C–C bond formation of bromoarenes with diazo compounds and malonates was developed. Various bromoarenes ranging from benzenoids to azines and heteroles were transformed to the corresponding...

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We have discovered a ring-opening fluorination of bicyclic azaarenes. Upon treatment of bicyclic azaarenes such as pyrazolopyridines with electrophilic fluorinating agents, fluorination of the aromatic ring is followed by a...

Pd-catalyzed asymmetric dearomative arylation of C3-substituted indoles is realized via a desymmetrization strategy. A BINOL-derived chiral phosphoramidite ligand is found to be highly efficient for the stereoselective control in this reaction. This method provides a convenient synthesis of spiroindolenines bearing two stereogenic centers in good yields (up to 98%) with excellent diastereo- and enantioselectivities (up to >20:1 dr and 97% ee), which could also be applied in asymmetric dearomative arylation of the simple C3-tethered indoles.

A ring-opening fluorination of isoxazoles has been developed. Upon treatment of isoxazoles with an electrophilic fluorinating agent (Selectfluor), fluorination followed by deprotonation leads to tertiary fluorinated carbonyl compounds. This method features mild reaction conditions, good functional group tolerance, and a simple experimental procedure. Diverse transformations of the resulting α-fluorocyanoketones were also demonstrated, furnishing a variety of fluorinated compounds.