Bulky P,P=O ligands were designed to inhibit isomerization and reduction side reactions during the cross coupling between sterically hindered aryl halides and alkylboronic acids. Suzuki-Miyaura cross-couplings between di-ortho-substituted aryl bromides and acyclic secondary alkylboronic acids have been achieved with high yields. The method has also enabled the preparation of ortho-alkoxy di-ortho-substituted arenes bearing isopropyl groups in excellent yields. The utility of the synthetic method has been demonstrated in a late-stage modification of estrone and in the application to a new synthetic route toward gossypol.

An asymmetric strategy for the construction of chiral sulfur-containing spirooxindole-fused heterocycles was achieved via a rhodium(II)/chiral phosphoric acid-cocatalyzed reaction between 2-mercaptophenyl ketones and 3-diazooxindoles. With this method, a series of spirooxindole-thiaindan derivatives bearing two contiguous quaternary carbon stereogenic centers were obtained in high yields with high diastereoselectivities and high-to-excellent enantioselectivities.

Enantioenriched γ-butenolides are valuable structural cores in many pharmaceuticals and natural products, but their direct and catalytically asymmetric assembly remains rare. Here, we report an efficient, atom-economic synthetic strategy for enantioenriched γ-butenolides via a unique enantioselective reaction of cyclopropene carboxylic acids with imines under the synergistic catalysis of Rh 2 (esp) 2 / chiral Brønsted acid system. The reaction involved trapping of carboxylic oxonium ylides, generated from cyclopropene carboxylic acids, which presented as the first asymmetric trapping reactive intermediate in the process. Subsequently, enantioenriched γ-butenolide derivatives were obtained in good-to-high yields (55-94%) with excellent stereoselectivities (up to >95∶5 dr and up to 98∶2 er) under mild conditions.

Efficient sterically demanding aryl–alkyl Suzuki–Miyaura coupling between di-ortho-substituted aryl halides and secondary alkylboronic acids has been achieved with a Pd-AntPhos catalyst.