Übergangsmetallkatalysierte C-C-Kupplungen mit Ethylen im Labormaßstab

Nickel-Catalyzed Arylboration of Alkenylarenes: Synthesis of Boron-Substituted Quaternary Carbons and Regiodivergent Reactions

A method for the construction of boron-substituted quaternary carbons or diarylquaternary carbons by arylboration of highly substituted alkenylarenes is presented. A wide range of alkenes and arylbromides can participate in this reaction thus allowing for a diverse assortment of products to be prepared. In addition, a solvent dependent regiodivergent arylboration of 1,2-disubstituted alkenylarenes is presented, thus greatly increasing the scope of products that can be accessed.

Palladium-Catalyzed Enantioselective Alkenylation of Enelactams Using a Relay Heck Strategy

In this report, a palladium-catalyzed redox-relay Heck process to access optically active alkenylated α,β-unsaturated lactams is described. Under mild reaction conditions, electron-deficient alkenyl triflates and electron-rich alkenyl iodonium salts undergo enantioselective and site-selective coupling with enelactams to deliver the products in high yields and excellent enantioselectivities. Furthermore, the products allow facile access to natural products such as (+)-calvine and (+)-2-epicalvine in addition to the bioactive molecule aza-goniothalamin.

Acetonitrile Activation: An Effective Two-Carbon Unit for Cyclization

A novel activation of acetonitrile for the construction of cyclobutenones by [2+2] cyclization was developed. Acetonitrile is utilized for the first time as two-carbon (C2) cyclization building block. The present protocol successfully inhibits the competitive cycloaddition with the C≡N bond of acetonitrile, but enables the in situ formation of an unsaturated carbon-carbon bond and the subsequent cycloaddition as a C2 unit. This chemistry features simple reaction conditions, high chemoselectivities, wide substrate scope, and offers a new and practical approach to cyclobutenones and cyclobuteneimines.