Low‐Pressure Cobalt‐Catalyzed Enantioselective Hydrovinylation of Vinylarenes. Issue 22 (25th April 2016)

• Record Type: Journal Article
• Authors: Movahhed, Sohajl; Westphal, Julia; Dindaroğlu, Mehmet; Falk, Anna; Schmalz, Hans‐Günther
• Is Part Of: Chemistry. Volume 22:Issue 22(2016)
• Page Start: 7381
• Page End: 7384
• Publication Date: 2016-04-25
• Subjects: alkenes -- asymmetric catalysis -- C−C bond formation -- chirality -- cobalt; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201601283
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: An efficient and practical protocol for the enantioselective cobalt‐catalyzed hydrovinylation of vinylarenes with ethylene at low (1.2 bar) pressure has been developed. As precatalysts, stable [L2 CoCl2 ] complexes are employed that are activated in situ with Et2 AlCl. A modular chiral TADDOL‐derived phosphine–phosphite ligand was identified that allows the conversion of a broad spectrum of substrates, including heterocyclic vinylarenes and vinylferrocene, to smoothly afford the branched products with up to 99 % ee and virtually complete regioselectivity. Even polar functional groups, such as OH, NH2, CN, and CO2 R, are tolerated. Abstract : Combination of a chiral TADDOL‐derived phosphine–phosphite ligand with CoCl2 was the key for the development of a robust and reliable protocol for the enantioselective codimerization of various functionalized vinylarenes with ethylene (see scheme).