Cationic Iridium/S-Me-BIPAM-Catalyzed Direct Asymmetric Intermolecular Hydroarylation of Bicycloalkenes

Tomohiko Shirai; Yasunori Yamamoto

doi:10.1002/anie.201504563

Cationic Iridium/S-Me-BIPAM-Catalyzed Direct Asymmetric Intermolecular Hydroarylation of Bicycloalkenes

Angew Chem Int Ed Engl. 2015 Aug 17;54(34):9894-7. doi: 10.1002/anie.201504563. Epub 2015 Jul 1.

Authors

Tomohiko Shirai¹, Yasunori Yamamoto²

Affiliations

¹ Division of Chemical Process Engineering and Frontier Chemistry Center (FCC), Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8 Kita-ku, Sapporo, Hokkaido 060-8628 (Japan).
² Division of Chemical Process Engineering and Frontier Chemistry Center (FCC), Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8 Kita-ku, Sapporo, Hokkaido 060-8628 (Japan). yasuyama@eng.hokudai.ac.jp.

PMID: 26136308
DOI: 10.1002/anie.201504563

Abstract

Highly enantioselective cationic iridium-catalyzed hydroarylation of bicycloalkenes, by carbonyl-directed C-H bond cleavage, was accomplished using a newly synthesized sulfur-linked bis(phosphoramidite) ligand (S-Me-BIPAM). The reaction provides alkylated acetophenone or benzamide derivatives in moderate to excellent yields and good to excellent enantioselectivities. Notably, the hydroarylation reaction of 2-norbornene with N,N-dialkylbenzamide proceeds with excellent enantioselectivity (up to 99% ee) and high selectivity for the mono-ortho-alkylation product.

Keywords: alkenes; alkylation; asymmetric synthesis; iridium; synthetic methods.