-Dichlorobis(XPhos)palladium(II) Precatalyst for Suzuki-Miyaura Cross-Coupling Reactions of Aryl/Vinyl Sulfonates/Halides: Scope, Mechanistic Study, and Synthetic Applications.

Suzuki-Miyaura cross-coupling reactions of aryl/vinyl sulfonates/halides with various boron species were performed using an easily available -dichlorobis(XPhos)palladium(II) precatalyst. Under microwave assistance, more than 30 coupling products were obtained with yields ranging from 23 to 99%, including the synthesis of two bioactive compounds, dubamine and tamoxifen. A mechanistic investigation of the Suzuki-Miyaura reaction was conducted notably by nuclear magnetic resonance (NMR) and high-resolution mass spectroscopy, revealing the nature of the active Pd species and of the reducing entity.

Gold(I)-Catalyzed Synthesis of Furopyrans: Insight into Hetero-Diels-Alder Reactions.

We report herein the synthesis of complex molecules containing furopyran cores through a gold(I)-catalyzed hetero-Diels-Alder cascade reaction. During this process, the diene and the dienophile are produced concomitantly by the action of a single catalyst from a single starting material. Moreover, six bonds, four heterocycles, and four controlled stereogenic centers are formed in a one-step operation.

Benzosultam Synthesis by Gold(I)-Catalyzed Ammonium Formation/Nucleophilic Substitution.

The synthesis of benzosultams has been achieved through a gold(I)-catalyzed ammonium formation strategy. Starting from easily available -(2-alkynyl)phenylsulfonyl azetidine derivatives, a cyclization reaction generated a spiroammonium gold intermediate that was ring-opened by nucleophilic alcohol or indole. This new methodology is compatible with the large variation in the substrates and nucleophiles and allowed the formation of benzosultams in high yield (18-98%, 20 examples).