Silaborative Carbocyclizations of 1,7-Enynes. Diastereoselective Preparation of Chromane Derivatives

Palladium­(0)-catalyzed carbocyclization of 1,7-enynes mediated by (chlorodimethylsilyl)­pinacolborane proceeds with 1,8-addition of the silicon and boron functions to give functionalized cyclohexane derivatives with boron attached to the exocyclic olefin. A variety of chromane dervatives are accessible by this method. In contrast to the analogous reactions with 1,6-enynes, the configuration of the newly formed stereogenic center is controlled by a stereogenic center present in the substrate

Asymmetric Dearomatic Diels–Alder Reactions of Diverse Heteroarenes via π‑System Activation

An asymmetric dearomatic Diels–Alder protocol for various heteroarenes, such as benzofuran, benzothiophene, or even furan, has been developed via π-system activation. This method involves <i>in situ</i> generation of formal trienamine species embedding a heteroaromatic moiety, and an array of chiral fused frameworks with high molecular complexity and skeletal diversity were efficiently constructed in good to excellent stereoselectivity by the catalysis of a cinchona-based primary amine

Asymmetric Diels–Alder Reaction of 2‑Methyl-3-indolylmethanols via in Situ Generation of <i>o</i>‑Quinodimethanes

An asymmetric Diels–Alder reaction of 2-methyl-3-indolylmethanols and α,β-unsaturated aldehydes has been developed that relies on in situ generation of active indole-2,3-quinodimethane intermediates under mild acidic conditions and uses a secondary chiral amine as iminium activation catalyst. An array of highly enantioenriched tetrahydrocarbazoles have been efficiently produced in fair to good yields

Asymmetric Diels–Alder Reaction of 2‑Methyl-3-indolylmethanols via in Situ Generation of <i>o</i>‑Quinodimethanes

An asymmetric Diels–Alder reaction of 2-methyl-3-indolylmethanols and α,β-unsaturated aldehydes has been developed that relies on in situ generation of active indole-2,3-quinodimethane intermediates under mild acidic conditions and uses a secondary chiral amine as iminium activation catalyst. An array of highly enantioenriched tetrahydrocarbazoles have been efficiently produced in fair to good yields