Atypical Dearomative Spirocyclization of β-Naphthols with Diazoacetamides Using a Silver Catalyst

BF3·Et2O-assisted synthesis of sulfinylated spiro[5.5]trienones from biaryl ynones

Sulfinyls are valuable structural moieties used for developing synthetically new pharmaceuticals and agrochemicals. Herein, we disclose a straightforward synthesis of sulfinylated spiro[5.5]trienones proceeding via an unprecedented BF3·Et2O-promoted spirocyclization of biaryl ynones. The availability of relatively inexpensive BF3·Et2O to carry out transformations on a bulk scale along with its further application towards the synthesis of dibenzocyclohepten-5-ones delivers a unique opportunity to deploy it in various synthetic directions.

Highly enantioselective synthesis of norcaradiene derivatives from naphthyl diazoacetamides using a Ru(ii)-Pheox complex

The highly regio- and enantioselective intramolecular cyclopropanation reactions of naphthyl diazoacetamides have been reported herein.

Dearomative Cyclopropanation of Naphthols via Cyclopropene Ring-Opening

The dearomatization of 2-naphthols represents a simple method for the construction of complex 3D structures from simple planar starting materials. We describe a cyclopropanation of 2-naphthols that proceeds via cyclopropene ring-opening using rhodium and acid catalysis under mild conditions. The vinyl cyclopropane molecules were formed with high chemoselectivity and scalability, which could be further functionalized at different sites. Both computational and experimental evidence were used to elucidate the reaction mechanism.

Development of Novel Methodology Using Diazo Compounds and Metal Catalysts

The ability to control the reactions of highly active chemical species to enable straightforward synthesis of valuable compounds such as bioactive natural products and pharmaceuticals is a continuing challenge in synthetic organic chemistry. This review describes the development of a methodology using reactive metal-carbene species and its synthetic application in our laboratory. First, regioselective synthesis of γ-amino acid equivalents to take advantage of their metal-dependent reactivities and the mechanistic rationale are presented. Chemoselective and enantioselective dearomatization reactions of several arenes with silver-carbene are also discussed. In the second half of the review, we discuss a carbene-insertion reaction into an amide and urea C-N bond for the assembly of nitrogen-bridged cyclic molecules.